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Quantum-well (QW) hybrid organic-inorganic perovskite (HOIP) crystals, e.g. A2Pb2X4 (A = BA, PEA, X = Br, I), demonstrated significant potentials as scintillating materials for wide energy radiation detection compared to their individual three-dimensional (3D) counterparts, e. g. BPbX3 (B = MA). Inserting 3D into QW structures resulting new structures namely A2BPb2X7 perovskite crystals and they may have promising optical and scintillation properties towards higher mass density and fast timing scintillators. In this article, we investigate the crystal structure, optical and scintillation properties of iodide-based QW HOIP crystals, A2PbI4 and A2MAPb2I7. A2PbI4 crystals exhibit green and red emission with fastest PL decay time < 1 ns, while A2MAPb2I7 crystals exhibit high mass density of > 3.0 g/cm3, and tunable smaller band gaps < 2.1 eV resulting from quantum and dielectric confinement. We observe that only PEA cation-based A2MAPb2I7 shows emission under X- and γ-ray excitations. We further observe that QW HOIP iodide scintillators exhibit shorter radiation absorption length (~3 cm at 511 keV) and faster decay time component (~0.5 ns) compared to QW HOIP bromide scintillators. We investigate the light yields of both QW HOIP crystals (> 7 photons/keV) at 10 K, while at room temperature are still low > 0.6 photons/keV compared to our previously reported QW bromide crystals (10-40 photons/keV). Thus, promising results of our study on iodide-based QW HOIP scintillators provide the right pathway for further enhancement towards fast-timing applications.

We present the measurements of the photoionization cross sections of the excited

In this work we demonstrated the process of co-deposition of copper-tin sulfide species by the atomic layer deposition (ALD) technique using all-low-cost precursors. For the deposition of tin species, the tin(IV) chloride SnCl4 was used successfully for the first time in the ALD process. Moreover, we showed that the successful deposition of the tin sulfide component was conditioned by the pre-deposition of CuS x layer. The co-deposition of copper and tin sulfides components at 150 °C resulted in the in-process formation of the film containing Cu2SnS3, Cu3SnS4 and π-SnS phases. The process involving only tin precursor and H2S did not produce the SnS x species. The spectroscopic characteristic of the obtained materials were confronted with the literature survey, allowing us to discuss the methodology of the determination of ternary and quaternary sulfides purity by Raman spectroscopy. Moreover, the material characterisation with respect to the morphology (SEM), phase composition (XRD), surface chemical states (XPS), optical properties (UV–vis-NIR spectroscopy) and electric (Hall measurements) properties were provided. Finally, the obtained material was used for the formation of the p–n junction revealing the rectifying I–V characteristics.

The recordings of speech in enclosures are corrupted by reverberation caused by multipath wave propagation from the speaker to the distant microphones. In this letter, we address the problem of reducing the late part of room reverberation. The presented blind dereverberation method consists in multichannel linear prediction (MCLP) and enforces sparsity of the dereverberated speech by adopting the split Bregman approach. The proposed algorithm alternately solves two optimization problems, where the former cost function is derived by assuming that speech is modelled using a sparse prior distribution, while the latter optimization emphasizes speech sparsity by an additional incorporation of a weighted $\ell _1$ -norm of the output signal to the standard linear prediction based cost function. The results of experiments performed using simulated and measured room impulse responses for various reverberation time values indicate superior performance of the proposed sparse split Bregman (SSB) method over state-of-the-art non-sparse and sparse MCLP-based dereverberation methods in terms of standard evaluation measures and as pre-processsing to the automatic speech recognition.

Purpose Inflammatory mechanisms have been suggested to play a role in the heart failure with reduced ejection fraction (HF-REF) development, but the role of chemokines is largely unknown. Cardiac resynchronization therapy (CRT) may reverse the HF-REF course. We aimed to evaluate selected chemokines concentrations in HF-REF patients and their relationship with disease severity and clinical response to CRT. Materials and methods The study included 37 patients (64.1 ± 11.04 years, 6 females) with HF-REF subjected to CRT, controlled prior to implantation and after 6 months. The control population included 26 healthy volunteers (63.9 ± 8.1 years, 8 females). Serum chemokines concentrations were determined using multiplex method. Results HF-REF patients were characterized by the higher baseline MIF, NAP-2 and PF4 concentrations and lower Axl, BTC, IL-9, and IL-18 BPa concentrations comparing to controls. After 6 months of CRT only NAP-2 concentration decreased significantly in comparison to the baseline values. Conclusions HF-REF patients present altered chemokines profile compared to the control group. The CRT-related alleviation of HF-REF causes only slight changes in the chemokines concentrations especially in the platelet-associated ones. The precise chemokines role in the HF-REF pathogenesis and their prognostic value remains to be established.

Vibrational spectroscopy coupled with isotopic labeling provides many insights into dynamic processes within various molecular systems. Here, a newfound utility of surface-enhanced Raman scattering (SERS) spectroscopy as a tool to study noble metal-anchored thiol monolayers is demonstrated for a pair of L-cysteine isotopologues competing to bind the surface of silver nanoparticles (AgNPs). According to our DFT calculations, SERS spectra of L-Cys could be sensitive to 12C/13C and 14N/15N isotopic substitutions, which has been experimentally confirmed for the pair of L-Cys isotopologues: Cys-cabn (all 12C/14N) and Cys-CABN (all 13C/15N). In the AgNP-anchored state, the two isotopologues reveal distinct Raman shift values (1577 cm-1 / 1633 cm-1) of the band assigned to C=O stretching. This characteristic SERS feature has been subsequently employed to probe various exchange scenarios between AgNP-bound and free L-Cys molecules. As the exchange involves two spectrally distinct but chemically identical molecules, the process is exclusively entropy-driven ultimately leading to the equilibrium state in which Cys-cabn/Cys-CABN concentration ratios in the Ag surface-bound layers and the bulk solution are identical. In a system containing AgNP-L-Cys and an excess of free L-Cys molecules, the exchange energy barrier limits the overall kinetics. Although the SERS-monitored rate of progression toward the equilibrium state under ambient conditions (25 °C) is negligible, a very steep acceleration of the exchange is observed at 50 °C. While the temperature-induced transition is very abrupt, it is still reversible with cooling. We argue that the dramatic acceleration of the dynamics of the L-Cys exchange between free and AgNP-bound molecules may be rationalized as a collective phase transition to an excited and reaction-prone state. Our work highlights unexplored potential of SERS spectroscopy coupled to isotopic exchange as a tool to study obscured dynamic phenomena within metal-anchored adsorbate layers.

We present an open-source hardware and software ecosystem for optical atomic clocks. We provide PCB schematics and fabrication files for manufacturing the most important electronic systems together with the required software. The boards are designed for an active bad-cavity superradiant strontium clock and a passive optical lattice strontium clock, but they can be easily adapted to other atomic species’ optical atomic clocks or ultra-cold atoms’ systems like magneto-optical traps or Bose–Einstein condensate setups.

International audience; Recent developments in quantum technology have resulted in a new generation of sensors for measuring inertial quantities, such as acceleration and rotation. These sensors can exhibit unprecedented sensitivity and accuracy when operated in space, where the free-fall interrogation time can be extended at will and where the environment noise is minimal. European laboratories have played a leading role in this field by developing concepts and tools to operate these quantum sensors in relevant environment, such as parabolic flights, free-fall towers, or sounding rockets. With the recent achievement of Bose–Einstein condensation on the International Space Station, the challenge is now to reach a technology readiness level sufficiently high at both component and system levels to provide “off the shelf” payload for future generations of space missions in geodesy or fundamental physics. In this roadmap, we provide an extensive review on the status of all common parts, needs, and subsystems for the application of atom-based interferometers in space, in order to push for the development of generic technology components.

We present the measurements of the photoionisation cross sections of the excited $^1$P$_1$ and $^3$S$_1$ states of ultracold $^{88}$Sr atoms at 389.889 nm wavelength, which is the magic wavelength of the $^{1}$S$_{0}$-${}^{3}$P${}_{0}$ clock transition. The photoionisation cross section of the $^1$P$_1$ state is determined from the measured ionisation rates of $^{88}$Sr in the magneto-optical trap in the $^1$P$_1$ state to be 2.20(50)$\times$10$^{-20}$ m$^2$, while the photoionisation cross section of $^{88}$Sr in the $^3$S$_1$ state is inferred from the photoionisation-induced reduction in the number of atoms transferred through the $^3\text{S}_1$ state in an operating optical lattice clock to be $1.38(66)\times$10$^{-18}$ m$^2$. Furthermore, the resulting limitations of employing a blue-detuned magic wavelength optical lattice in strontium optical lattice clocks are evaluated. We estimated photoionisation induced loss rates of atoms at 389.889 nm wavelength under typical experimental conditions and made several suggestions on how to mitigate these losses. In particular, the large photoionisation induced losses for the $^3$S$_1$ state would make the use of the $^3$S$_1$ state in the optical cycle in a blue-detuned optical lattice unfeasible and would instead require the less commonly used $^3$D$_{1,2}$ states during the detection part of the optical clock cycle., Comment: Copyright 2022 Optica Publishing Group. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved