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Oxygen is a unique molecule that possesses a spin quantum number S=1. In the condensed phases of oxygen, the delicate balance between the antiferromagnetic interaction and van der Waals force results in the various phases with different crystal structures. By applying ultrahigh magnetic fields, the antiferromagnetic coupling between O2 molecules breaks, and novel high-field phases can appear. We have investigated the physical properties of condensed oxygen under ultrahigh magnetic fields and have found that the stable crystal structure of solid oxygen changes around 100 T. Even in liquid oxygen, we observed a strong acoustic attenuation, which indicates the fluctuation of local molecular arrangements. These results demonstrate that magnetic fields can modulate the packing structure of oxygen through spin-lattice coupling. Our study implies the possibility of controlling oxygen-related (bio-)chemical processes by using an external magnetic field.

We report dielectric, thermodynamical, acoustic, and optical properties of a chiral molecular crystal, 1,1'-bi-2-naphthol 2-dimethylsulfoxide (BINOL2DMSO). We find two successive phase transitions at Tc1=190 K and Tc2=125 K. The first transition at Tc1 is characterized by an order-disorder transition of the guest molecules DMSO along with ferroelectricity. At the second transition of Tc2, the crystal structure deforms from tetragonal to monoclinic, leading to domain formation. Low-temperature x-ray diffraction suggests that the space group changes from P4_12_12 (P4_32_12) to P4_1 (P4_3) at Tc1, and down to P112_1 at Tc2., 16 pages, 10 figures

Magnetic properties of an antiferromagnetic double perovskite oxide ${\mathrm{Ba}}_{2}{\mathrm{CaReO}}_{6}$, where ${\mathrm{Re}}^{6+}$ $(5{d}^{1})$ ions with large spin-orbit coupling are arranged on the face-centered-cubic lattice, are investigated using pulsed high magnetic field up to 66 T. Magnetization and magnetostriction measurements have revealed a magnetic field-induced phase transition at around 50 T. The phase transition accompanies a jump of magnetization and longitudinal magnetostriction of approximately $2\ifmmode\times\else\texttimes\fi{}{10}^{--4}$ with the change of power-law behavior, indicating sizable coupling between the electronic degrees of freedom and the lattice. The high-field phase exhibits a magnetic moment approximately 0.2 ${\ensuremath{\mu}}_{\mathrm{B}}$, which is close to the values observed in $5{d}^{1}$ double perovskite oxides with noncollinear magnetic structure. We argue that ${\mathrm{Ba}}_{2}{\mathrm{CaReO}}_{6}$ is an antiferromagnet that sits close to the phase boundary between the collinear and noncollinear phases, providing the target material for investigating the interplay between spin-orbital entangled electrons and magnetic field.

The Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, characterized by Cooper pairs condensed at finite momentum, has been a long-sought state that remains unresolved in many classes of fermionic systems, including superconductors and ultracold atoms. A fascinating aspect of the FFLO state is the emergence of periodic nodal planes in real space, but its observation is still lacking. Here we investigate the superconducting order parameter at high magnetic fields $H$ applied perpendicular to the $ab$ plane in a high-purity single crystal of FeSe. The heat capacity and magnetic torque provide thermodynamic evidence for a distinct superconducting phase at the low-temperature/high-field corner of the phase diagram. Despite the bulk superconductivity, spectroscopic-imaging scanning tunneling microscopy performed on the same crystal demonstrates that the order parameter vanishes at the surface upon entering the high-field phase. These results provide the first demonstration of a pinned planar node perpendicular to $H$, which is consistent with a putative FFLO state., 11 pages, 9 figures, including Supplemental Material. Accepted for publication in Phys. Rev. Lett

Magnetoresistance of the correlated narrow-gap semiconductor FeSi was investigated by the radio frequency self-resonant spiral coil technique in magnetic fields up to 500 T, which is supplied by an electromagnetic flux compression megagauss generator. Semiconductor-to-metal transition accomplishes around 270 T observed as a sharp kink in the magnetoresistance, which implies the closing of the hybridization gap by the Zeeman shift of band edges. In the temperature-magnetic field phase diagram, the semiconductor-metal transition field is found to be almost independent of temperature, which is in contrast to a characteristic magnetic field associated with the hopping magnetoconduction in the in-gap localized states, exhibiting a notable temperature dependence.

Spins behave quantum mechanically in solids. If there are strong interactions between spins, the effective repulsion force constraints the behavior of spins and intriguing quantum phenomena such as a magnon crystal, Bose-Einstein condensation (BEC), and spin liquid, appear when a magnetic field whose Zeeman energy is comparable to the interaction strength is applied at low temperatures. In the present study, such magnetic field induced quantum phase transitions have been investigated using ultrahigh magnetic fields exceeding 100 T. Specifically, the magnon crystals in SrCu2(BO3)2, the magnon BEC in TlCuCl3, and the spin liquid in a-RuCl3 were observed. In addition to the pure spin systems, systems that possess a strong spin-lattice coupling exhibit more variety of phenomena including structural phase transitions in the ultrahigh fields: The spin state BEC in LaCoO3 and the insulator-metal transition in V1-xWxO2 have been recently studied in magnetic fields of up to 600 T.

Single-turn coil (STC) technique is a convenient way to generate ultrahigh magnetic fields of more than 100 T. During the field generation, the STC explosively destructs outward due to the Maxwell stress and Joule heating. Unfortunately, the STC does not work at its full potential because it has already expanded when the maximum magnetic field is reached. Here, we propose an easy way to delay the expansion and increase the maximum field by using a mass-loaded STC. By loading clay on the STC, the field profile drastically changes, and the maximum field increases by 4 %. This method offers an access to higher magnetic fields for physical property measurements., Comment: 6 pages, 5 figures, Accepted in Review of Scientific Instruments

We devised a portable system that generates pulsed high magnetic fields up to 77 T with 3 $\mu$s duration. The system employs the single turn coil method, a destructive way of field generation. The system consists of a capacitor of 10.4 $\mu$F, a 30 kV charger, a mono air-gap switch, a triggering system, and a magnet clamp, which weighs less than 1.0 tons in total and is transportable. The system offers opportunities for single-shot experiments at ultrahigh magnetic fields in combinations with novel quantum beams. The single-shot x-ray diffraction experiment using x-ray free-electron laser at 65 T is presented. We comment on the possible update of the system for the generation of 100 T., Comment: 5 pages, 4 figures

We performed high-magnetic-field ultrasonic experiments on YbB$_{12}$ up to 59 T to investigate the valence fluctuations in Yb ions. In zero field, the longitudinal elastic constant $C_{11}$, the transverse elastic constants $C_{44}$ and $\left( C_{11} - C_{12} \right)/2$, and the bulk modulus $C_\mathrm{B}$ show a hardening with a change of curvature at around 35 K indicating a small contribution of valence fluctuations to the elastic constants. When high magnetic fields are applied at low temperatures, $C_\mathrm{B}$ exhibits a softening above a field-induced insulator-metal transition signaling field-induced valence fluctuations. Furthermore, at elevated temperatures, the field-induced softening of $C_\mathrm{B}$ takes place at even lower fields and $C_\mathrm{B}$ decreases continuously with field. Our analysis using the multipole susceptibility based on a two-band model reveals that the softening of $C_\mathrm{B}$ originates from the enhancement of multipole-strain interaction in addition to the decrease of the insulator energy gap. This analysis indicates that field-induced valence fluctuations of Yb cause the instability of the bulk modulus $C_\mathrm{B}$., 15 pages, 11 figures

Ultrasound is a powerful means to study numerous phenomena of condensed-matter physics as acoustic waves couple strongly to structural, magnetic, orbital, and charge degrees of freedom. In this paper, we present such a technique combined with single-turn coils (STCs) that generate magnetic fields beyond 100 T with the typical pulse duration of 6 μs. As a benchmark of this technique, the ultrasound results for MnCr2S4, Cu6[Si6O18]⋅6H2O, and liquid oxygen are shown. The resolution for the relative sound-velocity change in the STC is estimated as Δv/v ∼ 10−3, which is sufficient to study various field-induced phase transitions and critical phenomena.

Efficient cooling of trapped charged particles is essential to many fundamental physics experiments1,2, to high-precision metrology3,4 and to quantum technology5,6. Until now, sympathetic cooling has required close-range Coulomb interactions7,8, but there has been a sustained desire to bring laser-cooling techniques to particles in macroscopically separated traps5,9,10, extending quantum control techniques to previously inaccessible particles such as highly charged ions, molecular ions and antimatter. Here we demonstrate sympathetic cooling of a single proton using laser-cooled Be+ ions in spatially separated Penning traps. The traps are connected by a superconducting LC circuit that enables energy exchange over a distance of 9 cm. We also demonstrate the cooling of a resonant mode of a macroscopic LC circuit with laser-cooled ions and sympathetic cooling of an individually trapped proton, reaching temperatures far below the environmental temperature. Notably, as this technique uses only image–current interactions, it can be easily applied to an experiment with antiprotons1, facilitating improved precision in matter–antimatter comparisons11 and dark matter searches12,13., A single electromagnetically trapped proton is sympathetically cooled to below ambient temperature by coupling it through a superconducting LC circuit to a laser-cooled cloud of Be+ ions stored in a spatially separated trap.

The entire magnetization process of ${\mathrm{TlCuCl}}_{3}$ has been experimentally investigated up to 100 T employing the single-turn technique. The upper critical field ${H}_{c2}$ is observed to be 86.1 T at 2 K. A convex slope of the $M\text{\ensuremath{-}}H$ curve between the lower and upper critical fields (${H}_{c1}$ and ${H}_{c2}$) is clearly observed, which indicates that a particle-hole symmetry is broken in ${\mathrm{TlCuCl}}_{3}$. By quantum Monte Carlo simulation and the bond-operator theory method, we find that the particle-hole symmetry breaking results from strong interdimer interactions.

Purpose Giant pulmonary arterial aneurysm (PAA) is a rare but serious complication for patients with pulmonary hypertension (PH). Heart-lung transplantation or lung transplantation with a full length of donor pulmonary artery (PA) for pulmonary artery reconstruction (PAR) are options for PH complicated with a giant PAA involving PA trunk to main PAs. We have been using donor aorta for the reconstruction of PA for these lung transplant cases. This study aimed to describe our intermediate-term outcomes of lung transplantation with PAR using donor aorta for PH complicated with a giant PAA. Methods This is a single center retrospective review from March 2000 to May 2020. We reviewed cadaveric lung transplantations for PH and compared the outcomes of lung transplantation with PAR (PAR group) with those without PAR (non-PAR group). Results Twenty-five PH patients underwent cadaveric lung transplantation. Among them, 5 patients with a giant PAA underwent lung transplantation with PAR using donor aorta. Representative 3D-CT images of a giant PAA and the reconstructed PA are shown in Figure A. The diameter of the PA trunk was significantly larger in the PAR group compared to the non-PAR group (Figure B). As expected, operative time was significantly longer in the PAR group compared to the non-PAR group (PAR, 1204 minutes; non-PAR, 965 minutes, p=0.035). On the other hand, primary graft dysfunction grade, 30-day mortality (PAR, 0%; non-PAR, 5.0%), 5-year survival rate (PAR, 100%; non-PAR, 73.9%, Figure C), and 6 minutes walk distance at 1 year after lung transplantation (PAR, 522 m; non-PAR, 526m) were not significantly different between the groups. The donor aortas used for PAR did not show constriction, obstruction, enlargement, or infection during the observation period. Conclusion Our experience supports that lung transplantation with PAR using donor aorta is a feasible surgical option for PH complicated with a giant PAA.

The multiferroic nature of the honeycomb-lattice $\mathrm{M}{\mathrm{n}}_{2}{\mathrm{V}}_{2}{\mathrm{O}}_{7}$ was investigated through detailed temperature, high-pressure, and magnetic-field-dependent measurements. A first-order martensiticlike structural phase transition with the thermal hysteresis associated with magnetic, heat-capacity, and dielectric anomalies was observed between ${T}_{Mh}$ (303 K) and ${T}_{Mc}$ (291 K). External pressure up to 15.41 kbar suppresses the thermal hysteresis in the magnetization data, indicating that the high-temperature \ensuremath{\beta}-phase persists down to the lower temperature under 15.41 kbar. Furthermore, isothermal capacitance-stress hysteresis loops along with crystallographic Aizu notation of $2/mF\overline{1}$ supports a martensitic phase transition driving ferroelastic ordering near or below room temperature. At low temperature, a long-range antiferromagnetic ordering was observed at ${T}_{N}\ensuremath{\sim}17\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. With increasing the external pressure up to 15.41 kbar, 100% enhancement of ${T}_{N}$ was observed and a metamagnetic transition at 5 K was enhanced near 3 T. High-field magnetization study up to 60 T induces multiple metamagnetic transitions below ${T}_{N}$. Below ${T}_{N}$, a magnetostriction induced magnetoelectric coupling was observed and further supported by the temperature-dependent x-ray studies. Taking these comprehensive research findings into account, we established that $\mathrm{M}{\mathrm{n}}_{2}{\mathrm{V}}_{2}{\mathrm{O}}_{7}$ is a unique multifunctional material with the coexistence of ferroelastic and antiferromagnetic orderings and with weak magnetoelectric coupling.

We conducted the coincidence measurement of $\alpha$ particles inelastically scattered from ${}^{20}$Ne at $0^{\circ}$ and decay charged particles in order to search for the alpha-particle condensed state. We compared the measured excitation-energy spectrum and decay branching ratio with the statistical-decay-model calculations, and found that the newly observed states at $E_x$ = 23.6, 21.8, and 21.2 MeV in ${}^{20}$Ne are strongly coupled to a candidate for the 4$\alpha$ condensed state in ${}^{16}$O. This result presents the first strong evidence that these states are the candidates for the 5$\alpha$ condensed state., Comment: 6 pages, 5 figures. The part of the analysis is updated, and some discussions are added

As a new method to determine the resonance frequency, Rabi-oscillation spectroscopy has been developed. In contrast to the conventional spectroscopy which draws the resonance curve, Rabi-oscillation spectroscopy fits the time evolution of the Rabi oscillation. By selecting the optimized frequency, it is shown that the precision is twice as good as the conventional spectroscopy with a frequency sweep. Furthermore, the data under different conditions can be treated in a unified manner, allowing more efficient measurements for systems consisting of a limited number of short-lived particles produced by accelerators such as muons. We have developed a fitting function that takes into account the spatial distribution of muonium and the spatial distribution of the microwave intensity to apply the new method to ground-state muonium hyperfine structure measurements at zero field. This was applied to the actual measurement data and the resonance frequencies were determined under various conditions. The result of our analysis gives $\nu_{\rm HFS}=4\ 463\ 301.61 \pm 0.71\ {\rm kHz}$, which is the world's highest precision under zero field conditions., Comment: 6 pages, 5 figures

Near surface indium arsenide quantum wells have recently attracted a great deal of interest since they can be interfaced epitaxially with superconducting films and have proven to be a robust platform for exploring mesoscopic and topological superconductivity. In this work, we present magnetotransport properties of two-dimensional electron gases confined to an indium arsenide quantum well near the surface. The electron mass extracted from the envelope of the Shubnikov-de Haas oscillations shows an average effective mass $m^{*}$ = 0.04 at low magnetic field. Complementary to our magnetotransport study, we employed cyclotron resonance measurements and extracted the electron effective mass in the ultra high magnetic field regime. Our measurements show that the effective mass depends on magnetic field in this regime. The data can be understood by considering a model that includes non-parabolicity of the indium arsenide conduction bands.

Single shot x-ray diffraction (XRD) experiments have been performed with a x-ray free electron laser (XFEL) under pulsed high magnetic fields up to 16 T generated with a nondestructive minicoil. The antiferromagnetic insulator phase in a perovskite manganaite, Pr$_{0.6}$Ca$_{0.4}$MnO$_{3}$, is collapsed at a magnetic field of $\approx 8$ T with an emergence of the ferromagnetic metallic phase, which is observed via the accompanying lattice changes in a series of the single shot XRD. The feasibility of the single shot XRD experiment under ultrahigh magnetic fields beyond 100 T is discussed, which is generated with a portable destructive pulse magnet., 6 pages, 5 figures

A hydrogen-like atom consisting of a positive muon and an electron is known as muonium. It is a near-ideal two-body system for a precision test of bound-state theory and fundamental symmetries. The MuSEUM collaboration performed a new precision measurement of the muonium ground-state hyperfine structure at J-PARC using a high-intensity pulsed muon beam and a high-rate capable positron counter. The resonance of hyperfine transition was successfully observed at a near-zero magnetic field, and the muonium hyperfine structure interval of ${\nu}_{\text{HFS}}$ = 4.463302(4) GHz was obtained with a relative precision of 0.9 ppm. The result was consistent with the previous ones obtained at Los Alamos National Laboratory and the current theoretical calculation. We present a demonstration of the microwave spectroscopy of muonium for future experiments to achieve the highest precision., Comment: 7 pages, 8 figures

A simple method for measuring electrical resistivity under destructive pulsed magnetic fields is presented. This method uses pick-up voltage as the power source to allow the measurement of the absolute value of resistivity in ultra-high magnetic fields above 100 T. The experimental setup and its operation are described in detail, and its performance is demonstrated using critical field measurements of thin-film FeSe0.5Te0.5 samples. Possible scientific applications of this setup in high magnetic fields as well as in any other environment with a high field sweep rate are also discussed.

Metal-insulator (MI) transitions in correlated electron systems have long been a central and controversial issue in material science. Vanadium dioxide (VO2) exhibits a first-order MI transition at 340 K. For more than half a century, it has been debated whether electronic correlation or the structural instability due to dimerised V ions is the more essential driving force behind this MI transition. Here, we show that an ultrahigh magnetic field of 500 T renders the insulator phase of tungsten (W)-doped VO2 metallic. The spin Zeeman effect on the d electrons of the V ions dissociates the dimers in the insulating phase, resulting in the delocalisation of electrons. Because the Mott-Hubbard gap essentially does not depend on the spin degree of freedom, the structural instability is likely to be the more essential driving force behind the MI transition., Comment: 9 pages, 9 figures (including the supplementary information)

High magnetic field x-ray diffraction experiments of solid oxygen have been performed at 10 K using DC magnetic fields of up to 5 T as well as pulsed magnetic fields of up to 25 T. The $\ensuremath{\alpha}$ phase of oxygen exhibits no magnetostriction greater than $\mathrm{\ensuremath{\Delta}}d/d={10}^{\ensuremath{-}4}$ at 5 T, where $d$ and $\mathrm{\ensuremath{\Delta}}d$ denote a lattice plane spacing and its magnetic field variation, respectively. The $\mathrm{\ensuremath{\Delta}}d/d$ at higher fields of up to 25 T is found to be smaller than $2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$. These results contradict the previously reported giant magnetostriction in the $\ensuremath{\alpha}$ phase where the volume magnetostriction $\mathrm{\ensuremath{\Delta}}V/V$ reaches ${10}^{\ensuremath{-}2}$ at 7.5 T [K. Katsumata et al., J. Phys.: Condens. Matter 17, L235 (2005)].

We report a very rare case of pulmonary chromomycosis caused by Scedosporium prolificans that developed after lung transplantation and was successfully treated with endobronchial topical amphotericin B instillation. The subject was a woman in her 50s with a history of bilateral lobar lung transplantation from living donors for idiopathic pulmonary hypertension. Eight years after the lung transplantation, chest radiography X-ray and computed tomography showed an abnormal shadow in the right lung. Bronchoscopic findings showed obstruction by a fungal component at the laterobasal bronchus B9. She was diagnosed with pulmonary chromomycosis after S. prolificans was detected in the bronchial aspirate. Systemic antifungal treatment with itraconazole was ineffective. Therefore, we administered topical amphotericin B weekly via endobronchial instillation and replaced oral itraconazole with voriconazole. The endobronchial procedure was safe and tolerable. Bronchial obstruction improved after three 3 instillations. We continued topical amphotericin B instillation once every 3 months for 2 years, and the abnormal shadow nearly disappeared. This case report describes infection by S. prolificans, which rarely becomes an etiologic agent in lung transplant patients, and shows that endobronchial topical amphotericin B instillation is a therapeutic option when systemic antifungal treatment is ineffective.

Occlusion of the common carotid artery (CCA) is rare. CCA occlusion (CCAO) can present as drowsiness and right hemiplegia related to emboli after total arch replacement. Although we selected a follow-up at first because color duplex sonography showed retrograde flow from the left external carotid artery to the internal carotid artery, this patient had epilepsy and single-photon emission computed tomography (SPECT) acquired quantitative results of actual brain perfusion and showed insufficient collateral blood flow. To improve brain perfusion, we performed a bypass of the left subclavian artery to left CCA bypass. Postoperatively, the patient did not have epilepsy and drowsiness. Also, right hemiplegia improved enough for him to walk with support. SPECT showed increased left cerebral flow (the asymmetry ratio was 71% to 81%). Evaluation of the carotid artery with color duplex sonography alone was insufficient when CCAO showed retrograde or collateral flow. We should have performed quantitative evaluation with SPECT at the same time.

The triple alpha reaction is one of the most important reactions in the nuclear astrophysics. However, its reaction rate in high temperature environments at T 9 > 2 was still uncertain. One of the major origins of the uncertainty was that the radiative-decay probability of the 3 1 − state in 12C was unknown. In the present work, we have determined the radiative-decay probability of the 3 1 − state to be 1.3 − 1.1 + 1.2 × 10 − 6 by measuring the 1H(12C,12Cp) reaction for the first time, and derived the triple alpha reaction rate in high temperature environments from the measured radiative-decay probability. The present result suggests that the 3 1 − state noticeably enhances the triple alpha reaction rate although the contribution from the 3 1 − state had been assumed to be small.

High-speed 100 MHz strain monitor using fiber Bragg grating (FBG) and an optical filter has been devised for the magnetostriction measurements under ultrahigh magnetic fields. The longitudinal magnetostriction of LaCoO$_{3}$ has been measured at room temperature, 115, 7 and 4.2 K up to the maximum magnetic field of 150 T. The field-induced lattice elongations are observed, which are attributed to the spin-state crossover from the low-spin ground state to excited spin-states., Comment: 4 pages, 2 figures, proceedings of SCES 2017

Acentric and nonpolar $\mathrm{P}{\mathrm{b}}_{2}\mathrm{Mn}{\mathrm{O}}_{4}$ was predicted to exhibit unique multipiezo induced magnetoelectric (ME) phenomena. In this paper, we present the results of magnetization as well as dielectric properties as a function of temperature (T), magnetic field (H), pressure (P), and electric field (E) primarily to address the ME coupling and identify the underlying mechanism behind this phenomenon. Magnetization and specific-heat measurements reveal the antiferromagnetic ordering of $\mathrm{M}{\mathrm{n}}^{4+}$ spins at temperature ${T}_{N}=17\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. Metamagnetic transitions at three critical magnetic fields (${H}_{c1}$, ${H}_{c2}$, and ${H}_{c3}$) are observed for T ${T}_{N}$ and H g 3.5 T. Further, the influences of pressure and magnetic field on ${H}_{c1}$ and ${H}_{c2}$ are investigated. The ${T}_{N}$, ${H}_{c1}$, and ${H}_{c2}$ all decrease with increasing external pressure. The dielectric anomaly observed at ${T}_{N}$ is influenced by applying a magnetic field of H g 3.5 T. However, the electric field has minimal influence on the metamagnetic transition. The scaling between dielectric constant and magnetization meaningfully resolves the existence of magnetic-field-induced higher-order ME coupling in $\mathrm{P}{\mathrm{b}}_{2}\mathrm{Mn}{\mathrm{O}}_{4}$ at T ${T}_{N}$ and H g 3.5 T.

Microscopic spin interactions on a deformed kagome lattice of volborthite are investigated through magnetoelastic couplings. A negative longitudinal magnetostriction $\mathrm{\ensuremath{\Delta}}L/Ll0$ in the $b$ axis is observed, which depends on the magnetization $M$ with a peculiar relation of $\mathrm{\ensuremath{\Delta}}L/L\ensuremath{\propto}{M}^{1.3}$. Based on the exchange striction model, it is argued that the negative magnetostriction originates from a pantographlike lattice change of the Cu-O-Cu chain in the $b$ axis, and that the peculiar dependence arises from the local spin correlation. This idea is supported by DFT+$U$ calculations simulating the lattice change and a finite-size calculation of the spin correlation, indicating that the recently proposed coupled-trimer model is a plausible one.

The antihydrogen program of the ASACUSA collaboration at the antiproton decelerator of CERN focuses on Rabi-type measurements of the ground-state hyperfine splitting of antihydrogen for a test of the combined Charge–Parity–Time symmetry. The spectroscopy apparatus consists of a microwave cavity to drive hyperfine transitions and a superconducting sextupole magnet for quantum state analysis via Stern–Gerlach separation. However, the small production rates of antihydrogen forestall comprehensive performance studies on the spectroscopy apparatus. For this purpose a hydrogen source and detector have been developed which in conjunction with ASACUSA’s hyperfine spectroscopy equipment form a complete Rabi experiment. We report on the formation of a cooled, polarized, and time modulated beam of atomic hydrogen and its detection using a quadrupole mass spectrometer and a lock-in amplification scheme. In addition key features of ASACUSA’s hyperfine spectroscopy apparatus are discussed. The antihydrogen programme of the ASACUSA collaboration at the antiproton decelerator of CERN focuses on Rabi-type measurements of the ground-state hyperfine splitting of antihydrogen for a test of the combined Charge-Parity-Time symmetry. The spectroscopy apparatus consists of a microwave cavity to drive hyperfine transitions and a superconducting sextupole magnet for quantum state analysis via Stern-Gerlach separation. However, the small production rates of antihydrogen forestall comprehensive performance studies on the spectroscopy apparatus. For this purpose a hydrogen source and detector have been developed which in conjunction with ASACUSA's hyperfine spectroscopy equipment form a complete Rabi experiment. We report on the formation of a cooled, polarized, and time modulated beam of atomic hydrogen and its detection using a quadrupole mass spectrometer and a lock-in amplification scheme. In addition key features of ASACUSA's hyperfine spectroscopy apparatus are discussed.t

The structure of the Λ(1405) hyperon is an important and long-standing issue related to the K-nucleus interaction. The J-PARC E31 experiment has been performed to investigate the Λ(1405) spectrum shape. Because it is hard to form the Λ(1405) directly by a KN scattering in free space, E31 uses the d(K-, n) reaction with an incident kaon momentum of 1 GeV/c. We will identify three final states - ς-π+, ς+π-, ς0π0-so that the isospin structure of hyperon resonance states produced can be decomposed. The first physics run of the E31 experiment was performed in 2016. To enhance the statistics of the data set, we have performed the second physics run in the beginning of 2018. During the second run of E31, around 3.9×1010 kaons impacted on the deuteron target.

The properties of the Kondo insulator in a strong magnetic field are one of the most intriguing subjects in condensed matter physics. The Kondo insulating state is expected to be suppressed by magnetic fields, which results in the dramatic change in the electronic state. We have studied the magnetization process of one of the prototypical Kondo insulators YbB 12 at several temperatures in magnetic fields of up to 80 T. The metamagnetism due to the insulator-metal (IM) transition seen around 50 T was found to become significantly broadened at approximately 30 K. This characteristic temperature T * &asymp, 30 K in YbB 12 is an order of magnitude lower than the Kondo temperature T K = 240 K. Our results suggest that there is an energy scale smaller than the Kondo temperature that is important to understanding the nature of Kondo insulators.

The megagauss laboratory, ISSP, UTokyo has a long history of generation of megagauss fields, especially using the electro-magnetic flux compression, originated from the original work in 1970s. We have initiated a new project of 1000 T since 2011, and since then, we have been devoting ourselves to installation of the system and the technical improvements. Condenser bank units with 20 kV, 2 MJ for seed feed coils, and two set of main condenser bank units, 5MJ and 2 MJ each with 50 kV charging capability. The system comprising of those condenser modules has been installed, and operation tuning has been completed. The giant collector plates, and load coil clamping units are installed in anti-explosion chambers. Design of all those instruments was optimized to substantial improvement of the electro-magnetic field energy conversion efficiency. Our recent results of record magnetic field 1200 T obtained from our new megagauss generating systems is presented.

Effects of ultrahigh magnetic fields on the electronic state of $\mathrm{V_{1-x} W_{x}O_{2} (x=0.06)}$ are investigated. Optical transmission increases with decreasing temperature due to the transformation from the high-temperature metallic state to the low-temperature insulating state. We have made optical transmission measurements with 2 μm wavelength laser light, and found that the low-temperature insulating state is suppressed by ultrahigh magnetic fields exceeding around 100 T.

We have conducted magnetization measurements of the $S = 1$ spin-ladder compound BIP-TENO using the single-turn coil method which generates micro-second pulsed magnetic field. We observed three magnetization plateaus in the magnetization process up to 100 T. We have also found that the magnetization process depends on the sweep speed of the magnetic fields. Possible origins of this phenomenon are (1) lowering temperature of the samples due to magnetocaloric effect with adiabatic condition realized in the fast (micro-second) pulsed magnetic field, and (2) spin-lattice separation due to a slow response of the magnetostriction whose response time is longer than microsecond range.

The contactless high-frequency electrical conductivity measurement using a “self-resonant” probe coil was performed under the ultra-high magnetic fields generated by the destructive magnets, and applied to measure the upper critical field of the cuprate superconductor La 1.84 Sr 0.16 CuO 4 , and also applied to observe a semiconductor-metal transition of the narrow gap semiconductor FeSi.

The specific heat of the Kondo insulator ${\mathrm{YbB}}_{12}$ has been measured up to 60 T. The Sommerfeld coefficient $\ensuremath{\gamma}$ significantly increases at around 50 T, where the insulator metal transition occurs with a steep increase of the magnetization. $\ensuremath{\gamma}$ reaches $67\text{ }\text{ }\mathrm{mJ}/(\mathrm{mol}\text{ }{\mathrm{K}}^{2})$ at high fields, which directly indicates that the quasiparticles gain a heavy thermodynamic effective mass and transform into a Kondo metal under magnetic fields. The field-induced Kondo metal has a rather high Kondo temperature around 200 K. The strong Kondo coupling proves that the energy gap collapse does not correspond to the breakdown of the Kondo bound state. The steep increase of the magnetization at the transition manifests the sharp density of states at the Fermi energy formed via the Kondo resonance.