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Neutron imaging is one of the most powerful tools for nondestructive inspection owing to the unique characteristics of neutron beams, such as high permeability for many heavy metals, high sensitivity for certain light elements, and isotope selectivity owing to a specific nuclear reaction between an isotope and neutrons. In this study, we employed a superconducting detector, current-biased kinetic-inductance detector (CB-KID) for neutron imaging using a pulsed neutron source. We employed the delay-line method, and high spatial resolution imaging with only four reading channels was achieved. We also performed wavelength-resolved neutron imaging by the time-of-flight method for the pulsed neutron source. We obtained the neutron transmission images of a Gd-Al alloy sample, inside which single crystals of GdAl3 were grown, using the delay-line CB-KID. Single crystals were well imaged, in both shapes and distributions, throughout the Al-Gd alloy. We identified Gd nuclei via neutron transmissions that exhibited characteristic suppression above the neutron wavelength of 0.03 nm. In addition, the ^{155}Gd resonance dip, a dip structure of the transmission caused by the nuclear reaction between an isotope and neutrons, was observed even when the number of events was summed over a limited area of 15 X 12 um^2. Gd selective imaging was performed using the resonance dip of ^{155}Gd, and it showed clear Gd distribution even with a limited neutron wavelength range of 1 pm., 7 pages, 6 figures, Accepted in Journal of IEEE transactions of Applied Superconductivity

We performed a chirality-controlled crystal growth of transition metal disilicide NbSi$_{2}$ and TaSi$_{2}$ by using a laser-diode-heated floating zone (LDFZ) method. The crystal chirality was evaluated in the crystals of centimeters in length by performing single crystal X-ray diffraction as well as probing a spin polarization originating from chirality-induced spin selectivity (CISS) effect. The crystals of right-handed NbSi$_{2}$ and of left-handed TaSi$_{2}$ were obtained in the conventional LDFZ crystal growth, while the left-handed NbSi$_{2}$ and right-handed TaSi$_{2}$ crystals were grown by the LDFZ method with the composition-gradient feed rods. The spin polarization via the CISS was observed over centimeters in the NbSi$_{2}$ single crystals and the sign of the CISS signals was dependent on the chirality of crystals. The correlation between the crystal chirality and CISS signals indicates that the CISS measurements work as a non-destructive method for chirality determination even in centimeter-long specimens., Comment: 9 pages, 6 figures

We report that spin polarization occurs over millimeters in polycrystalline bulk samples of chiral disilicide NbSi$_2$ and TaSi$_2$. As previously demonstrated in the experiments using single crystals of NbSi$_2$ and TaSi$_2$, electrical transport measurements allow detection of direct and inverse signals associated with the chirality-induced spin polarization even in the chiral polycrystals. The spin polarization signals also appear in nonlocal measurements, in which charge current flows only in the area millimeters away from the detection electrode. These data mean that the spin polarization phenomena occur regardless of the presence of crystalline grains in the polycrystals, indicating a robustness and resilience of the chirality-induced spin polarization. On the basis of the experimental data, we found that the sum rule holds for the spin transport signals. A distribution of handedness over the samples was determined on average in the polycrystals. While the mechanism of preserving the spin polarization over millimeters remains to be clarified, the present study may open up prospects of spin control and manipulation over macroscopic length scales using chiral materials., 6 pages, 5 figures

Extreme ultraviolet lithography (EUVL) is a main lithographic technology for cutting-edge node. Also, ArF lithography will continue to be used in conjunction with EUVL for advanced node production. Critical ArF imaging layers require photomasks with tight resolution and "rigid CD and Positional accuracy". Those specifications are tightening due to the narrow process window. The etching process for phase-shifter has to precisely controlled to achieve the targets. . Various pattern density in PSM (Phase-Shifter Mask) shows phase angle variation due to the digging of the Quartz substrate(QZ). In the high transmittance PSM, the error has larger impact on the lithography due to strong phase shift effects. To prevent phase shift error from the target phase angle, QZ etching stop film is considered. It is possible to obtain a high etching selectivity compared with QZ and to apply an aggressive dry etching condition. In order to control in-plane phase angle distribution due to QZ etching during PSM etching, we proposed a novel high transmission etching stop film for ArF lasers.

In rare-earth permanent magnets, magnetization and Curie temperature are mainly dominated by 3d-electrons of Fe-group elements, and magnetic anisotropy arises from 4f-electrons, typically as an outcome from the combination of the crystal field effect and the spin-orbit interaction (SOI). Here we propose enhancement of an intrinsic coercivity due to the valence fluctuation derived from the 4f-electrons in Ce-based rare-earth magnets. Valence-fluctuations combined with SOI bring an effective magnetic anisotropy driven by kinetic energy in the hybridization of delocalized 4f-electrons and conduction electrons. This kinetic-energy-driven anisotropy has an order of magnitude stronger energy scale than the magnetic anisotropy driven by potential energy of well localized 4f-electrons in the crystal fields. The relatively strong coupling between 4f-3d electrons make such kinetic-energy driven anisotropy robust against high temperatures. This mechanism of intrinsic magnetic anisotropy is not only scientifically intriguing but also promising for application to permanent magnets., International Conference on Strongly Correlated Electron Systems (SCES 2020/21)

A spin-polarized state is examined under charge current at room temperature without magnetic fields in chiral disilicide crystals NbSi_{2} and TaSi_{2}. We found that a long-range spin transport occurs over ten micrometers in these inorganic crystals. A distribution of crystalline grains of different handedness is obtained via location-sensitive electrical transport measurements. The sum rule holds in the conversion coefficient in the current-voltage characteristics. A diamagnetic nature of the crystals supports that the spin polarization is not due to localized electron spins but due to itinerant electron spins. A large difference in the strength of antisymmetric spin-orbit interaction associated with 4d electrons in Nb and 5d ones in Ta is oppositely correlated with that of the spin polarization. A robust protection of the spin polarization occurs over long distances in chiral crystals.

Wide energy range neutron imaging and spectroscopy in a single experiment without changing the setup is available by a combination of a high-power pulsed neutron source and fast operating neutron detector. The delay-line current-biased kinetic-inductance detector (CB-KID) is a two-dimensional superconducting detector with high spatial and temporal resolutions, and multi-hit tolerance. We demonstrate that the delay-line CB-KID with 10B neutron conversion layer is applicable for neutron imaging and spectroscopy up to the neutron energy of 100 eV. High spatial neutron transmission image for a Sm-Sn mixed metal is successfully constructed below 0.3 eV. Concomitantly, we examine the neutron transmission up to 100 eV and identify observed resonance dips by Sm nuclei.

This study investigates a current-biased kinetic inductance detector (CB-KID) performance by investigating Bragg-edge spectra from the restricted-area neuron transmission of materials. Iron samples with a size of 5 × 5 ×2 mm3 were used as typical test materials. The ergodic theorem was used to obtain a visible transmission spectrum so that a long-time averaging of a transmission spectrum can alternatively be evaluated using a space average of independently selected area spectra with the same ensemble size. The most visible edges were observed with a limited area sample of 0.43 mm2 using a minimum time bin of 25 μs in a time-of-flight (ToF) spectrum or a wavelength resolution of 0.0007 nm of each neutron pulse at beamline BL10 of the Japan Proton Accelerator Research Complex (J-PARC) center. The main Bragg edge of iron as a sum of random 100 ensembles (with an ensemble size of 3.1 × 2.3 μm2) thus obtained has a distinctive signal-to-noise ratio and can be fitted well with the Rietveld Imaging of Transmission Spectra (RITS) program with Miller indices. We consider that our CB-KID system is, in principle, able to analyze the Bragg edge of samples as small as 3.1 × 2.3 μm2.

We grew thin films of a heavy fermion chiral magnet YbNi$_3$Al$_9$ by using molecular beam epitaxy. They were grown on $c$-plane sapphire substrates under ultra-high vacuum while maintaining a deposition rate at a stoichiometric ratio among Yb, Ni, and Al. The resulting thin films contain epitaxial grains with a $c$ axis parallel to the substrate surface: The YbNi$_3$Al$_9$ $c$ axis is parallel to the sapphire $b$ or $a$ axis. The temperature dependence of the resistivity exhibits a typical feature of a dense Kondo system with a broad shoulder structure at $\sim$40\,K, as well as a kink as a signature of the chiral helimagnetic ordering at 3.6\,K. These features are consistent with those previously observed in bulk samples. The shift in the kink associated with the field-induced phase transition is found in the magnetoresistance curves under a magnetic field applied in the direction perpendicular to the $c$-axis. The magnetic phase diagram well reproduces that for the bulk crystals, implying that the chiral soliton lattice phase arises under magnetic fields, even in thin films.

The rising global human population and increased environmental stresses require a higher plant productivity while balancing the ecosystem using advanced nanoelectronic technologies. Although multifunctional wearable devices have played distinct roles in human healthcare monitoring and disease diagnosis, probing potential physiological health issues in plants poses a formidable challenge due to their biological complexity. Herein an integrated multimodal flexible sensor system is proposed for plant growth management using stacked ZnIn2S4(ZIS) nanosheets as the kernel sensing media. The proposed ZIS-based flexible sensor can not only perceive light illumination at a fast response (∼4 ms) but also monitor the humidity with a perdurable steady performance that has yet to be reported elsewhere. First-principles calculations reveal that the tunneling effect dominates the current model associated with humidity response. This finding guides the investigation on the plant stomatal functions by measuring plant transpiration. Significantly, dehydration conditions are visually recorded during a monitoring period (>15 days). This work may contribute to plant-machine biointerfaces to precisely manage plant health status and judiciously utilize limited resources.

We have performed $^{59}$Co NMR measurements of CeCoIn$_5$ down to ultralow temperatures. We find that the temperature dependence of the spin-echo intensity provides a good measure of the sample temperature, enabling us to determine a pulse condition not heating up the sample by the NMR pulses down to ultralow temperatures. From the longitudinal relaxation time ($T_1$) measurements at 5 T applied along the $c$ axis, a pronounced peak in $1/T_1T$ is observed at 20 mK, implying an appearance of magnetic order as suggested by the recent quantum oscillation measurements [H. Shishido {\it et al.}, Phys. Rev. Lett. {\bf 120}, 177201 (2018)]. On the other hand, the NMR spectrum shows no change below 20 mK. Moreover, the peak in $1/T_1 T$ disappears at 6 and 8 T in contrast to the results of the quantum oscillation. We discuss that an antiferromagnetic state with a moment lying in the $a$--$b$ plane can be a possible origin for the peak in $1/T_1 T$ at 5 T., 9 pages, 10 figures; (v2) texts and figures updated; (v3) typo fixed, DOI and reference added

Chirality-induced spin transport phenomena are investigated at room temperature without magnetic fields in a monoaxial chiral dichalcogenide CrNb_{3}S_{6}. We found that spin polarization occurs in these chiral bulk crystals under a charge current flowing along the principal c axis. Such phenomena are detected as an inverse spin Hall signal which is induced on the detection electrode that absorbs polarized spin from the chiral crystal. The inverse response is observed when applying the charge current into the detection electrode. The signal sign reverses in the device with the opposite chirality. Furthermore, the spin signals are found over micrometer length scales in a nonlocal configuration. Such a robust generation and protection of the spin-polarized state is discussed based on a one-dimensional model with an antisymmetric spin-orbit coupling.

Neutron imaging is one of the key technologies for non-destructive transmission testing. Recent progress in the development of intensive neutron sources allows us to perform energy-resolved neutron imaging with high spatial resolution. Substantial efforts have been devoted to developing a high spatial and temporal resolution neutron imager. We have been developing a neutron imager aiming at conducting high spatial and temporal resolution imaging based on a delay-line neutron detector, called the current-biased kinetic-inductance detector, with a conversion layer $^{10}$B. The detector allowed us to obtain a neutron transmission image with four signal readout lines. Herein, we expanded the sensor active area, and improved the spatial resolution of the detector. We examined the capability of high spatial resolution neutron imaging over the sensor active area of 15 $\times$ 15 mm$^2$ for various samples, including biological and metal ones. We also demonstrated an energy-resolved neutron image in which stainless-steel specimens were discriminating of other specimens with the aid of the Bragg edge transmission., 17 pages, 6 figures

We present nuclear spin-lattice relaxation rate (1/T1) at the Co site and ac-susceptibility results in the normal and superconducting (SC) states of CeCoIn5 for H || c near the SC upper critical field Hc2 above 0.1 K. At 4.2 T, 1/T1 rapidly decreases below the SC transition temperature, consistent with the previous reports. Although the field dependence of 1/T1T at 0.1 K shows a peak at 5.2 T above Hc2, the temperature dependence of 1/T1T at 5.2 T is independent of temperature below 0.2 K, showing a Fermi-liquid behavior. In addition, we found no NMR-spectrum broadening by the appearance of internal fields around Hc2 at 0.1 K. We could not detect any field-induced magnetic instability around Hc2 down to 0.1 K although the remarkable non-Fermi-liquid behavior towards Hc2 was observed in various physical quantities., 6 pages, 3 figures

We report a vector-scanning SQUID microscope for probing a vector magnetic field. We designed and fabricated a vector [three-dimensional (3-D)] SQUID sensor with the aid of Nb multilayer fabrication technology. Our vector SQUID sensor on a single chip is composed of a vector sensor with three orthogonal pick-up coils, which catch the X , Y, and Z magnetic field components. We improved both the sensitivity and the spatial resolution not only by reducing the inner diameter but also by increasing the number of pick-up-coil windings within the framework of the multilayer technique. Our SQUID sensors operated properly, and the characteristics showed a good agreement with our design parameters. Since the sensor is suitable for our SQUID microscope, we are constructing our scanning microscope platform by using a Gifford-McMahon cryocooler for allowing long-time measurements. We also succeeded in connecting our vector SQUID sensor to a commercial flux-locked loop readout circuit (Magnicon Inc., Model XXF-1) to generate the voltage outputs, which are proportional to the XYZ components of the external magnetic field. We also use an XYZ piezo-driven scanner for the precise control of the pick-up-coil positions over the 3-D range of 5 × 5 × 5 mm 3 with a step size of 10 nm at 4 K.

Samples were examined using a superconducting (Nb) neutron imaging system employing a delay-line technique which in previous studies was shown to have high spatial resolution. We found excellent correspondence between neutron transmission and scanning electron microscope (SEM) images of Gd islands with sizes between 15 and 130 micrometer which were thermally-sprayed onto a Si substrate. Neutron transmission images could be used to identify tiny voids in a thermally-sprayed continuous Gd2O3 film on a Si substrate which could not be seen in SEM images. We also found that neutron transmission images revealed pattern formations, mosaic features and co-existing dendritic phases in Wood's metal samples with constituent elements Bi, Pb, Sn and Cd. These results demonstrate the merits of the current-biased kinetic inductance detector (CB-KID) system for practical studies in materials science. Moreover, we found that operating the detector at a more optimal temperature (7.9 K) appreciably improved the effective detection efficiency when compared to previous studies conducted at 4 K. This is because the effective size of hot-spots in the superconducting meanderline planes increases with temperature, which makes particle detections more likely., Comment: 19 pages, 6 figures

The current-biased kinetic-inductance detector (CB-KID) is a solid-state superconducting neutron detector with high spatial and temporal resolutions, and multi-hit tolerance. We demonstrate high temperature operation of CB-KID at 7.9 K with the delay-line method. High temperature operation reduces imaging pixel size by suppressing signal propagation velocity. High spatial neutron transmission image for a mixed metal alloy consisting of heavy elements Sm and Sn is successfully constructed. We also examine the capability of element discrimination imaging based on the resonance dip analysis.

Although the incidence of hepatobiliary enzyme abnormality increased immediately after the Great East Japan Earthquake and subsequent Fukushima Daiichi Nuclear Power Plant accident, longer-term trends remain unclear. The aims of this study were to determine longer-term trends in hepatobiliary enzyme abnormality and to elucidate lifestyle factors associated with such changes among residents of a nuclear-disaster-affected area. This longitudinal survey enrolled 20,395 adults living in the vicinity of Fukushima Daiichi Nuclear Power Plant. Data were obtained from the records of annual health checkups of adults aged ≥40 years between 2011 and 2012. Follow-up examinations were conducted from June 2013 to March 2014. Associations were assessed between changes in hepatobiliary enzyme abnormality immediately and 3–4 years after the disaster and lifestyle factors. The overall prevalence of hepatobiliary enzyme abnormality significantly decreased over the study period, from 29.9% to 27.1%. Multivariate logistic regression analysis revealed significant associations between improved hepatobiliary enzyme abnormality and improvements in daily physical activity and frequency of breakfast consumption. The results suggest that improvements in daily physical activity and frequency of breakfast consumption significantly reduced the incidence of hepatobiliary enzyme abnormality 3–4 years after the Great East Japan Earthquake and Fukushima Daiichi Nuclear Power Plant accident.

Background About 146,000 people were forced into long-term evacuation due to the nuclear power plant accident caused by the Great East Japan Earthquake in 2011. Disaster is known to induce hypertension in survivors for a certain period, but it is unclear whether prolonged disaster stress influences chronic kidney disease (CKD). We conducted an observational cohort study to elucidate the effects of evacuation stress on CKD incidence. Methods Participants were individuals living in communities near the Fukushima nuclear power plant, aged 40–74 years without CKD as of their 2011 general health checkup (non-evacuees: n = 9780, evacuees: n = 4712). We followed new-onset CKD [estimated glomerular filtration rate (eGFR)

We investigated vortex states in small star-shaped Mo 80 Ge 20 plates both theoretically and experimentally. The numerical calculations of the Ginzburg–Landau equation have been carried out with the aid of the finite element method, which is convenient to treat an arbitrarily shaped superconductor. The experimental results were observed by using a scanning SQUID microscope. Through systematic measurements, we figured out how vortices form symmetric configuration with increasing the magnetic field. The vortex distribution tends to adapt to one of five mirror symmetric lines when vortices were located at the five triangular horns of a star-shaped plate. The crystalline homogeneity of a sample was confirmed by the X-ray diffraction and the superconducting properties so that vortices are easily able to move for accommodating vortices in the geometric symmetry of the star-shaped plate. The experimental vortex configurations obtained for a star-shaped plate are in good agreement with theoretical predictions from the nonlinear Ginzburg–Landau equation.

Thoracic outlet syndrome (TOS) is one of the common neurovascular disorders of the upper extremities, and the compression or traction of the brachial plexus is the main pathology. We hypothesized that baseball players are more likely to be affected by TOS compared with other overhead-throwing athletes because of strenuous use of their throwing arm. The purpose of this study was to investigate the prevalence and clinical characteristics of TOS in high school baseball players. One thousand two hundred eighty-eight high school baseball players were included in this study. The prevalence of symptomatic TOS and its association to disorders of the upper extremities were investigated. The prevalence of symptomatic TOS was 32.8%. Age- and position-adjusted logistic regression analysis revealed that subjects with symptomatic TOS were at significantly higher risk of shoulder and/or elbow pain (odds ratio [OR]: 1.96, 95% confidence interval [CI]: 1.50 - 2.58) and a higher recurrence rate of shoulder and/or elbow pain during the previous season (OR: 2.38, 95% CI: 1.87 - 3.04). As for physical findings, subjects with symptomatic TOS were also at significantly higher risk of MUCL tenderness (OR: 2.53, 95% CI: 1.83 - 3.50), positive milking maneuver, (OR: 2.63, 95% CI: 1.78 - 3.91), positive subacromial impingement sign (OR: 1.92, 95% CI: 1.20 - 3.07), and positive posterior impingement sign (OR: 2.34, 95% CI: 1.67 - 3.28) compared to the subjects without symptomatic TOS. It is necessary to recognize that TOS is not a rare pathology in overhead-throwing athletes, especially baseball players, and that players with symptomatic TOS are at significantly higher risk of shoulder/elbow pain.

We successfully derived the time-dependent flux of pulsed neutrons using a superconducting Nb-based current-biased kinetic inductance detector (CB-KID) with a 10 B conversion layer at Japan Proton Accelerator Research Complex. Our CB-KID is a meander line made of a 40-nm-thick Nb thin film with 1 − μ m line width, which is covered with a 150-nm-thick 10 B conversion layer. The detector works at a temperature below 4 K. The evaluated detection efficiency of the CB-KID in this experiment is 0.23 % at the neutron energy of 25.4 meV. The time-dependent flux spectra of pulsed neutrons thus obtained are in good agreement with the results obtained by the Monte Carlo simulations.

This paper shows the latest challenges facing mask blank evolution to support leading-edge lithography processes. ArF immersion lithography has been employing multi-pass exposures to exceed the physical diffraction limit. These photomasks demand very accurate overlay, higher NILS and best CD uniformity for wider process window. The subject was considered from two perspectives from a mask blank producer, which are the mask-making perspective and the wafer lithography perspective. To improve the overlay, we introduced the dedicated CDL (Charge Dissipation Layer) for improving mask registration error. From the lithography resolution perspective, we have developed a high-transmittance phase-shifter film for higher NILS. CDU stability point of view, we described “Superior pattern fidelity CAR”, “High ArF durability SiN phase-shifter” and “Transparent etching stopper”. The industry decided to move to EUV lithography. But there are still many challenges for optical lithography.

Ce$_{2}$PtIn$_{8}$ is a recently discovered heavy-fermion system structurally related to the well-studied superconductor CeCoIn$_{5}$. Here, we report on low-temperature de Haas-van Alphen-effect measurements in high magnetic fields in Ce$_{2}$PtIn$_{8}$ and Pr$_{2}$PtIn$_{8}$. In addition, we performed band-structure calculations for localized and itinerant Ce-$4f$ electrons in Ce$_{2}$PtIn$_{8}$. Comparison with the experimental data of Ce$_{2}$PtIn$_{8}$ and of the $4f$-localized Pr$_{2}$PtIn$_{8}$ suggests the itinerant character of the Ce-$4f$ electrons. This conclusion is further supported by the observation of effective masses in Ce$_{2}$PtIn$_{8}$, which are strongly enhanced with up to 26 bare electron masses., 10 pages, 12 figures

Recent progress in the development of intensive neutron sources and the required peripheral equipment has enabled high-spatial-resolution neutron imaging that is simultaneously energy-resolved. The authors demonstrate a high-speed neutron-imaging system with a cutting-edge superconducting detector. This detector has the potential not just for applications requiring high spatial resolution, but also for two-dimensional detectors for other kinds of beams, by adopting an adequate conversion layer.

We previously succeeded in constructing and demonstrating the capability of a neutron imaging system based on a superconducting current-biased kinetic inductance detector (CB-KID). In the present work, we systematically studied the characteristics of the superconducting neutron detector to improve the spatial resolution and detection efficiency. We found that the number of neutron detection events with CB-KID remarkably increased when the detector temperature increased from 4 K to the critical temperature T c. We observed systematic changes of neutron signals as a function of the detector temperature from 4 K to T c. We evaluated the detection efficiency of the CB-KID detector, and compared with PHITS Monte Carlo simulations, which modeled the sequential physical processes for the 10B(n,α)7Li reaction, the transport dynamics, and the energy deposition by particles including neutrons, 4He particles, 7Li particles, photons, and electrons.

We demonstrate the development of an energy resolved neutron transmission imaging system via a solid-state superconducting detector, called current-biased kinetic-inductance detector (CB-KID). CB-KIDs comprise X and Y superconducting Nb meanderlines with Nb ground plane and a 10B conversion layer, which converts a neutron to two charged particles. High-energy charged particles are able to create quasi-particle hot spots simultaneously in the X and Y meander lines, and thus, the local Cooper pair density in meander lines is reduced temporary. When DC-bias currents are fed into the meander lines, double pairs of voltage pulses are generated at the hot spots and propagate toward both ends of the meander lines as electromagnetic waves. The position of the original hot spot is determined by a difference in arrival times of the two pulses at the two ends for X and Y meander lines, independently. This is so-called the delay-line method, and allows us to reconstruct the two-dimensional neutron transmission image of a test sample with four signal readout lines. We examined the capability of high spatial and energy (wavelength) resolved neutron transmission imaging over the sensor active area of 15 ×15 mm2 for various samples, including biological and metal ones. We also demonstrated the capability for the Bragg edge transmission and an energy-resolved neutron image in which stainless-steel specimens were discriminating from other specimens.

We succeeded in demonstrating a neutron detector based on a Nb superconducting meander line with a 10B conversion layer for a neutron imager based on superconductor devices. We use a current-biased kinetic inductance detector (CB-KID), which is composed of a meander line, for detection of a neutron with high spatial resolution and fast response time. The thickness of Nb meander lines is 40 nm and the line width is narrower than 3 mu m. The area of 8 mm × 8 mm is covered by CB-KIDs, which are assembled at the center of the Si chip of the size 22 mm × 22 mm. The Nb CB-KIDs with a 10B conversion layer output the voltage by irradiating pulsed neutrons. We have investigated γ/n discrimination of a Nb-based CB-KID with 10B conversion layer using a Cd plate, which indicates that a CB-KID can operate as a neutron detector under the strong γ-ray fields.

We perform de Haas--van Alphen (dHvA) measurements of the heavy-fermion superconductor ${\mathrm{CeCoIn}}_{5}$ down to 2 mK above the upper critical field. We find that the dHvA amplitudes show an anomalous suppression, concomitantly with a shift of the dHvA frequency, below the transition temperature ${T}_{n}=20\text{ }\text{ }\mathrm{mK}$. We suggest that the change is owing to magnetic breakdown caused by a field-induced antiferromagnetic (AFM) state emerging below ${T}_{n}$, revealing the origin of the field-induced quantum critical point (QCP) in ${\mathrm{CeCoIn}}_{5}$. The field dependence of ${T}_{n}$ is found to be very weak for 7--10 T, implying that an enhancement of AFM order by suppressing the critical spin fluctuations near the AFM QCP competes with the field suppression effect on the AFM phase. We suggest that the appearance of a field-induced AFM phase is a generic feature of unconventional superconductors, which emerge near an AFM QCP, including ${\mathrm{CeCoIn}}_{5}$, ${\mathrm{CeRhIn}}_{5}$, and high-${T}_{c}$ cuprates.

We perform de Haas-van Alphen (dHvA) measurements of the heavy-fermion superconductor CeCoIn_{5} down to 2 mK above the upper critical field. We find that the dHvA amplitudes show an anomalous suppression, concomitantly with a shift of the dHvA frequency, below the transition temperature T_{n}=20 mK. We suggest that the change is owing to magnetic breakdown caused by a field-induced antiferromagnetic (AFM) state emerging below T_{n}, revealing the origin of the field-induced quantum critical point (QCP) in CeCoIn_{5}. The field dependence of T_{n} is found to be very weak for 7-10 T, implying that an enhancement of AFM order by suppressing the critical spin fluctuations near the AFM QCP competes with the field suppression effect on the AFM phase. We suggest that the appearance of a field-induced AFM phase is a generic feature of unconventional superconductors, which emerge near an AFM QCP, including CeCoIn_{5}, CeRhIn_{5}, and high-T_{c} cuprates.

A superconducting nanowire detector with a 10 B conversion layer is useful for sensing a single neutron at a high operation rate. We use 7 Li ion and 4 He ion emitted as two independent heat sources in opposite direction, which are associated with nuclear reaction 10 B(n, 4 He) 7 Li to identify the XV position of neutron arrival. We probe a change rate in the kinetic inductance L k originating from kinetic inertia of the Cooper pairs. Our detector is different from a well-known microwave kinetic inductance detector and, hence, is named as a current-biased kinetic inductance detector. We use two sets of meanderlines made of Nb nanowires with superconducting readout taps to monitor local signals. In between the X meander and the V meander, we sandwiched a 10 B layer acting as a neutron conversion layer to two charged particles. We succeeded in observing signal induced by nuclear reaction. We plan to build a megapixel neutron imager by coupling 10-bit linear position-sensitive arrays with single-flux quantum circuits to read (X,V) position of neutron arrival in the future.

We grow thin films of SmB6 by molecular beam epitaxy under ultra-high vacuum better than 1×10−6Pa. Sm and B were evaporated independently by Knudsen cells with the deposition rate ratio of B and Sm as B/Sm in between 4.0 and 5.7 on an MgO (100) substrate with the substrate temperature of 1000 ∘C. Reflection high energy electron diffraction patterns show spotted ones indicating a relatively flat film surfaces. This is in good agreement with the surface roughness measured by the atomic force microscope. Interplane and inplane X-ray diffraction measurements represent the preference growth of c-axis oriented SmB4 thin films with the ratio B/Sm = 4.0. We obtained SmB6 thin films with the ratio B/Sm in between 4.9 and 5.7. X-ray diffraction measurements clarify that our SmB6 thin films show evidence of partial epitaxial growth as major domains orienting along [100]SmB6 ∥ [100]MgO. Crystallinity of inplane alignment is improved with approaching the stoichiometric deposition rate of B/Sm = 6. The electrical resistivity increases with decreasing temperature as a semiconductor, and becomes constant at low temperatures. These features well reproduce the tendency observed for the resistivity of bulk samples.

Since the progress in the fabrication techniques of thin-films of exotic materials such as strongly correlated heavy-fermion compounds, microscopic studies of the magnetic and electronic properties inside the films have been needed. Herein, we report the first observation of 115In nuclear quadrupole resonance (NQR) in an epitaxial film of the heavy-fermion superconductor CeCoIn5, for which the microscopic field gradient within the unit cell as well as magnetic and superconducting properties at zero field are evaluated. We find that the nuclear spin-lattice relaxation rate in the film is in excellent agreement with that of bulk crystals, whereas the NQR spectra show noticeable shifts and significant broadening indicating a change in the electric-field distribution inside the film. The analysis implies a displacement of In layers in the film, which however does not affect the magnetic fluctuations and superconducting pairing. This implies that inhomogeneity of the electronic field gradient in the film sample causes no pair breaking effect., 12 pages, 6 figures

Diabetes & Metabolism - In Press.Proof corrected by the author Available online since mardi 7 novembre 2017

We present not the results but the idea of a superconducting nanowire detector with $$^{10}$$ B conversion layer for sensing a single neutron. We use $$^{7}$$ Li ion and $$^{4}$$ He ion emitted as two independent heat sources, which appear in opposite direction associated with nuclear reaction $$^{10}$$ B(n, $$^{4}$$ He) $$^{7}$$ Li. We probe a change in the kinetic inductance $$L_\mathrm{k}$$ coming from inertia of the Cooper pairs. Our detector is different from a conventional kinetic inductance detector (KID), but is named as a current-biased KID. We use two sets of Nb nanowires with superconducting readout taps to monitor the local signal. In between the X meander and the Y meander, we inserted a $$^{10}$$ B layer acting as a conversion layer from neutrons to charged particles. We plan to fabricate a mega-pixel neutron imager by coupling 10 bit linear position-sensitive arrays along the X and Y directions with the single flux quantum readout circuits.

We recently proposed the idea of a novel sort of superconducting detector, i.e., a current-biased kinetic inductance detector (CB-KID). This detector is different from a current-biased transition edge detector studied previously, and is able to sense a change in kinetic inductance $$L_k$$ given by $$L_{k} = \Lambda _{k}l/S = m_{s}l/n_{s}{q_{s}}^{2}S$$ ( $$\Lambda _{k}$$ ; kinetic inductivity, $$m_s$$ ; mass of Cooper pair, $$n_s$$ ; density of Cooper pairs, $$q_s$$ ; charge of Cooper pair, $$l$$ ; length of device, $$S$$ ; cross sectional area) under a constant dc bias current $$I_b$$ . In the present work, we first extend this idea to construct a multi-channel CB-KIDs array made of 200-nm-thick MgB $$_2$$ thin-film meanderline with 3- $$\upmu $$ m thin wire. We succeeded in observing clear signals for imaging from the four-channel CB-KIDs at 4 K by irradiating focused pulsed laser. A scanning laser spot can be achieved by an XYZ piezo-driven stage and an optical fiber with an aspheric focused lens. We can see typical signals from all 4 channels at 4 K, and obtain the positional dependence of the signal as the contour in XY plane. Our CB-KIDs can be used as neutron detectors by utilizing energy released from a nuclear reaction between $$^{10}$$ B and cold neutron.

We mounted a vector-scanning superconducting quantum interference device (SQUID) sensor on a commercial SQUID microscope and successfully improved the sensitivity and spatial resolution of the sensor. Our proposed vector 3D SQUID sensor used multilayered Niobium (Nb)-based technology; we realized three SQUID sensors in the structure of a vector pickup coil system on a single chip. The vector pickup coil system was built with three pickup coils that were orthogonal to one another to obtain the alt;iagt;Xalt;/iagt;, alt;iagt;Yalt;/iagt;, and alt;iagt;Zalt;/iagt; components of a magnetic field vector. To improve both sensitivity and spatial resolution, we attempted to reduce the inner diameter by increasing the number of windings of the pickup coils using the multilayered Nb process. The design value for the dc SQUID sensors was either the critical current density alt;iagt;Jalt;/iagt;alt;subagt;calt;/subagt; = 320 A/cmalt;supagt;2alt;/supagt; for two Josephson junctions (JJs) or the critical current alt;iagt;Ialt;/iagt;alt;subagt;calt;/subagt; = 12.8 ?A for the 2 ?m × 2 ?m JJs. To measure the current?voltage (alt;iagt;I?Valt;/iagt;) and voltage?flux (alt;iagt;Valt;/iagt;??) characteristics of a sensor, we constructed a homemade measurement system. The fundamental characteristics of our SQUID sensors were in good agreement with the design parameters. We mounted our vector SQUID sensor on a commercial scanning SQUID microscope (SQM-2000, Seiko Instrument Inc.) with a single flux-locked loop (FLL) channel to test one of the three channels. We repeated the measurements three times to obtain the alt;iagt;Xalt;/iagt;, alt;iagt;Yalt;/iagt;, and alt;iagt;Zalt;/iagt; componential images of the magnetic field from a single vortex, and we synthesized the 3D mapping of the magnetic field vectors from a single vortex. We proved that our sensor mounted on a SQUID microscope was suitable for measuring the alt;iagt;Xalt;/iagt;, alt;iagt;Yalt;/iagt;, and alt;iagt;Zalt;/iagt; components of a vector magnetic field.

We are developing a new type of the neutron imager based on a superconducting neutron detector. We previously succeeded in constructing and demonstrating neutron detection capability of a superconducting current-biased kinetic inductance detector (CB-KID). In order to improve the spatial resolution and detection efficiency, the characteristics of a superconducting neutron detector have been studied systematically in the present work. As an extension of studying the characteristics of neutron detector, we investigated temperature dependence of neutron signal such as propagation velocity and the signal amplitude as a function of time of flight (ToF) with temperature. We consider that it is important to understand the temperature dependence of the signal to improve the spatial resolution and detection efficiency of a superconducting neutron detector.

We introduce a sectoral defect into a disk (creating a Pac-Man™-shaped plate) to investigate effect of the symmetry breaking of a perfect disk on vortex dynamics. The sectoral defect acts as a preferential gateway for vortices to enter the disk. Vortices tend to form a symmetric configuration with respect to the mirror-symmetry line under various different applied magnetic fields. We found that the vortex configuration of the Pac-Man™-shaped disk exhibits an exotic arc structure, in contrast to the well-known shell structure of a disk. A characteristic of the vortex configuration is the critical number of vortices (or 'magic number') at which the single-arc structure becomes a multiple-arc structure, which can be tuned by changing the opening angle of the sectoral defect. We also noticed by comparing the free energies of the vortex distributions, that there are several competing metastable states with the same number of vortices when the ratio of the number of vortices in the outer arc to the number in the inner arc approaches two, for which stable triangular clusters might form part of the configurations. We conclude that there are reasonable agreements between the Ginzburg–Landau calculations and experimental scanning SQUID microscope images of vortices in de facto mesoscopic Pac-Man™-shaped Mo80Ge20 thin disks.

Dramatic lifestyle changes due to the Fukushima Daiichi Nuclear Power Plant accident increased the prevalence of hepatobiliary enzyme abnormalities (HEA). We aimed to evaluate associations of HEA with specific lifestyle- and disaster-related factors in residents who lived near the Fukushima

The purpose of this study was to anatomically investigate the proximal origin of flexor–pronator muscles (FPMs) and clarify their contribution to dynamic stabilization of the elbow joint during valgus stress. 52 elbows from 26 donated formalin-fixed cadavers were examined. The pronator teres muscle (PT), flexor carpi radialis muscle (FCR), palmaris longus muscle (PL), flexor digitorum superficialis muscle (FDS), and flexor carpi ulnaris muscle (FCU) were identified, and their proximal origin and relationship to the anterior bundle of the medial ulna collateral ligament (AOL) were macroscopically and histologically investigated. The PT, FCR, PL, and FDS converged and formed a common tendon at their proximal origin (the anterior common tendon: ACT). The ACT was attached to the medial epicondyle and the joint capsule, just anterior and parallel to the AOL. The histological morphology of the ACT was quite similar to that of the AOL. The ulnar head of the PT was observed in 48 of 52 elbows (92.3 %), just behind the humeral head of PT. It mainly originated from the anterior edge of the sublime tubercle, while the upper part of ulnar head transitioned directly into the thickened joint capsule just anterior to the AOL. The proximal attachment of the FPMs had a characteristic morphology. According to our results, the ACT and PT might assist the AOL by sharing static and dynamic traction forces applied to the medial elbow joint.

The amorphous superconducting films, which tend to have weakened pinning centers, are remarkably useful as model substance in studying nanostructured superconductors. The amorphous Mo 80 Ge 20 films have been deposited by a sputtering apparatus using a Mo 80 Ge 20 target and the small Mo 80 Ge 20 plates were fabricated with the aid of photolithography. The vortex distribution in a Mo 80 Ge 20 disk has been investigated by means of a scanning SQUID microscope. We found that vortices form different configurations as well as shell structures, which evolves with the increase in applied magnetic fields. The observed results are in good agreement with theoretical studies predicted for vortices in mesoscopic circular disks. We also applied a novel numerical method to improve the spatial resolution of the scanning SQUID microscope.

There are few studies of the therapeutic effects of long-term corset wearing in patients with chronic low back pain. The aim of this study was to evaluate the effects of long-term corset wearing on chronic low back pain and to examine the myoelectrical activities of the paravertebral muscles. Forty subjects with chronic low back pain were enrolled and randomly divided into two groups: a group wearing corsets for 6 months (CW) group and a group not wearing corsets (NW). The treatment effects were measured using the Japanese Orthopaedic Association (JOA) score. Muscle endurance was evaluated during the Biering-Sorensen test (S-test), and the degree of muscle fatigue was evaluated by the change in percent mean power frequency (%MPF) of the paravertebral muscles. Corset treatment for chronic low back pain improved low back pain and increased muscle endurance for a short period of time. Paravertebral muscle fatigue was not increased by long-term corset wearing for chronic low back pain, and weakening of the paravertebral muscles was not observed up to 6 months after the start of corset wearing.

We have studied the superlattices with alternating block layers (BLs) of heavy-fermion superconductor CeCoIn5 and conventional-metal YbCoIn5 by site-selective nuclear magnetic resonance(NMR) spectroscopy, which uniquely offers spatially-resolved dynamical magnetic information. We find that the presence of antiferromagnetic fluctuations is confined to the Ce-BLs, indicating that magnetic degrees of freedom of f-electrons are quenched inside the Yb-BLs. Contrary to simple expectations that the two-dimensionalization enhances fluctuations, we observe that antiferromagnetic fluctuations are rapidly suppressed with decreasing Ce-BL thickness. Moreover, the suppression is more prominent near the interfaces between the BLs. These results imply significant effects of local inversion-symmetry breaking at the interfaces., 5 pages, 4 figures, accepted for publication as a Rapid Communication in Physical Review B