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Atomic-defect-suppressed pristine p-type Bi 0.3 Sb 1.7 Te 3 as robust high-performance thermoelectrics for power generation and cooling

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Journal of Materiomics 2025年

作者： Qi Zhao Zhen Fan Yi Wang Qiulin Liu Xuejuan Dong Xiaowei Wu Zhicheng Shan Hangtian Zhu Zhiliang Li Shufang Wang Huaizhou Zhao Hebei Key Lab of Optic-Electronic Information and Materials Key Laboratory of High-Precision Computation and Application of Quantum Field Theory of Hebei Province College of Physics Science and Technology Hebei University Baoding 071002 Hebei China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Science University of Chinese Academy of Sciences Beijing 100049 China

High-strength high-performance p-type (Bi,Sb) 2 Te 3 are of pivotal importance for near-room-temperature thermoelectric conversions, the reliable synthesis and fabrication has been viewed of imperative priority. It is known that the energy-favorable formation of anti-site Sb Te ' and vacancy v Sb ''' acceptor defects from high-temperature syntheses results in additional charge carriers and scattering centers for electrical and phonon transport. However, how p-type (Bi,Sb) 2 Te 3 with minimal lattice defects function remains to be scrutinized. Herein, we present the synergistic enhancements of mechanical robustness and thermoelectric property in crystallographic-defect-suppressed pristine (Bi,Sb) 2 Te 3 through a simple mechanical alloying combined with spark-plasma-sintering (SPS) process. The Sb Te ' and v Sb ''' acceptor defects were efficiently restrained, contributing to markedly increased charge carrier mobilities. A slightly enlarged band gap of 0.24 eV underpinned enhanced thermoelectric performance for pristine Bi 0.3 Sb 1.7 Te 3 over a wide temperature range, delivering high zT 300 K of 1.16 and zT ave of 1.21 over 300–473 K. Interestingly, the confined in-situ grain coarsening during SPS with uniform dispersive nanopores readily endowed an ultra-high compressive strength of 206 MPa, surpassing that of reported (Bi,Sb) 2 Te 3 so far. A 7-pair module (coupled with n-Bi 2 Te 3 ) was fabricated, demonstrating a competitive Δ T over 70 K at T hot = 300 K. Furthermore, a power-generation module coupled with n-Mg 3 SbBi registered a cutting-edge thermoelectric conversion efficiency of 9.5% at a temperature gradient of 250 K. The strategy eliminates the need of complex processing nor extrinsic doping for pristine (Bi,Sb) 2 Te 3 , demonstrating great potentials in thermoelectric power generation and cooling applications.

关键词： p-type (Bi,Sb) 2 Te 3 thermoelectric mechanial strength defect suppression band gap modulation

Holographic topological semimetals

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science China(physics,Mechanics & Astronomy) 2020年第5期63卷 6-30页

作者： Karl Landsteiner Yan Liu Ya-Wen Sun Instiuto de Fisica Teorica UAM/CSIC C/Nicolas Cabrera 13-15Campus CantoblancoCantoblanco 28049Spain Center for Gravitational Physics Department of Space ScienceBeihang UniversityBejing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Indusry and Information Technology.Beijing 100191China School of Physics&CAS Center for Excllence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100049China

The holographic duality allows to construct and study models of strongly coupled quantum matter via dual gravitational *** general such models are characterized by the absence of quasiparticles, hydrodynamic behavior and Planckian dissipation times. One particular interesting class of quantum materials are ungapped topological semimetals which have many interesting properties from Hall transport to topologically protected edge states. We review the application of the holographic duality to this type of quantum matter including the construction of holographic Weyl semimetals, nodal line semimetals, quantum phase transition to trivial states(ungapped and gapped), the holographic dual of Fermi arcs and how new unexpected transport properties,such as Hall viscosities arise. The holographic models promise to lead to new insights into the properties of this type of quantum matter.

关键词： gauge/gravity duality topological semimetal Weyl semimetal anomaly

Precisely Tuning Photothermal and Photodynamic Effects of Polymeric Nanoparticles by Controlled Copolymerization

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Angewandte Chemie 2020年第31期132卷 12856-12861页

作者： Wen K. Wu L. Wu X. Lu Y. Duan T. Ma H. Peng A. Shi Q. Huang H. College of Materials Science and Opto-Electronic Technology & Center of Materials Science and Optoelectronics Engineering & CAS Center for Excellence in Topological Quantum Computation & CAS Key Laboratory of Vacuum Physic University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Environment-friendly Energy Materials Sichuan Co-Innovation Center for New Energetic Materials School of National School of National Defence Science & Technology Southwest University of Science and Technology Mianyang 621010 China Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Dermatology & Guangdong Provincial Key Laboratory of Biomedical Imaging The Fifth Affiliated Hospital Sun Yat-sen University Zhuhai 519000 China

Cancer possesses normoxic and hypoxia microenvironments with different levels of oxygen, needing different efficacies of photothermal and photodynamic therapies. It is important to precisely tune the photothermal and photodynamic effects of phototherapy nano-agents for efficient cancer treatment. Now, a series of copolymeric nanoparticles (PPy-Te NPs) were synthesized in situ by controlled oxidative copolymerization with different ratios of pyrrole to tellurophene by FeCl3. The photothermal and photodynamic effects of semiconducting nano-agents under the first near-infrared (NIR) irradiation were precisely and systematically tuned upon simply varying the molar ratio of the pyrrole to tellurophene. The PPy-Te NPs were used for cancer treatment in mice, exhibiting excellent biocompatibility and therapeutic effect. This work presents a simple method to tune photothermal and photodynamic therapies effect in semiconducting nano-agents for cancer treatment. © 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

关键词： copolymerization photothermal/photodynamic effect polymeric nanoparticles pyrrole tellurium

Quantum Induced Coherence Light Detection and Ranging

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arXiv 2022年

作者： Qian, Gewei Xu, Xingqi Zhu, Shun-An Xu, Chenran Gao, Fei Yakovlev, V.V. Liu, Xu Zhu, Shi-Yao Wang, Da-Wei Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation Zhejiang Province Key Laboratory of Quantum Technology and Device School of Physics Zhejiang University Zhejiang Province Hangzhou310027 China ZJU-Hangzhou Global Science and Technology Innovation Center College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Texas A&M University 4242 TAMU College StationTX77840 United States Hefei National Laboratory Hefei230088 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing100190 China

Quantum illumination has been proposed and demonstrated to improve the signal-to-noise ratio (SNR) in light detection and ranging (LiDAR). When relying on coincidence detection, such a quantum LiDAR is limited by the response time of the detector and suffers from jamming noise. Inspired by the Zou-Wang-Mandel experiment, we design, construct and validate a quantum induced coherence (QuIC) LiDAR which is inherently immune to ambient and jamming noises. In traditional LiDAR the direct detection of the reflected probe photons suffers from deteriorating SNR for increasing background noise. In QuIC LiDAR we circumvent this obstacle by only detecting the entangled reference photons, whose single-photon interference fringes are used to obtain the distance of the object, while the reflected probe photons are used to erase path information of the reference photons. In consequence, the noise accompanying the reflected probe light has no effect on the detected signal. We demonstrate such noise resilience with both LED and laser light to mimic the background noise and jamming attack. The proposed method paves a new way of battling noise in precise quantum electromagnetic sensing and ranging. © 2022, CC BY.

关键词： Photons

Abundance analysis of stars hosting gas-rich debris disks

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arXiv 2025年

作者： Borthakur, Sandipan P.D. Kama, Mihkel Fossati, Luca Kral, Quentin Folsom, Colin P. Teske, Johanna Aret, Anna Tartu Observatory University of Tartu Observatooriumi 1 Tõravere61602 Estonia Space Research Institute Austrian Academy of Sciences Schmiedlstrasse 6 Graz8042 Austria Institute for Theoretical and Computation Physics Graz University of Technology Petersgasse 16 Graz8010 Austria Department of Physics and Astronomy University College London LondonWC1E 6BT United Kingdom LESIA Observatoire de Paris Université PSL CNRS Sorbonne Université Université Paris Cité 5 place Jules Janssen MeudonF-92195 France Earth and Planets Laboratory Carnegie Institution for Science 5241 Broad Branch Road NW WashingtonDC20015 United States

Context. Accretion from protoplanetary or debris disks can contaminate the stellar photosphere, especially in stars that have radiative envelopes. Due to relatively slower photospheric mixing, these stars can exhibit clear contamination signatures. The contaminated photosphere reflects ongoing disk processes, detectable through stellar spectroscopy. Aims. We investigate the composition of six gas-rich debris disk-hosting A-type stars to understand possible links with their debris disk or earlier accretion stages. Methods. We used archival spectra and the zeeman spectral synthesis code to estimate the stellar parameters and abundances of six debris disk-hosting A-type stars. We also estimated the stellar photospheric accretion contamination parameter, fph, using CAMstars which indicates the fraction of accreting material on the stellar photosphere. Results. The oxygen abundance in intermediate-mass stars decreases with age until the debris disk stage (2O ice accumulating in dust traps or the formation of hydrated asteroids in the protoplanetary disk, locking oxygen in solids and reducing its accretion onto the star. All stars have similar volatile abundances (C, O), but HD 110058 and HD 32297 show refractory depleted abundances. The near-zero fph values in the six stars suggest that any currently accreted gas would not overwhelm mixing in the photosphere, and would not impact the observed composition. The refractory depleted abundances in HD 110058 and HD 32297 suggest residual or even chronic, accretion contamination from their earlier protoplanetary stages when the accretion rates were about five orders of magnitude higher. For HD 110058, with the highest refractory depletion, we estimated a lower limit on its earlier protoplanetary accretion rate of 9 × 10−8 M/yr, similar to other Herbig stars and equal to the Herbig star - HD 100546. This supports our hypothesis that refractory depletion in HD 110058 originates from a prior phase of higher accretion of dust-poor

关键词： Planets

Black hole spectroscopy horizons for current and future gravitational wave detectors

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Physical Review D 2022年第4期105卷 044015-044015页

作者： Iara Ota Cecilia Chirenti Center for Natural and Human Sciences UFABC Santo André SP 09210-170 Brazil Department of Astronomy University of Maryland College Park Maryland 20742 USA Astroparticle Physics Laboratory NASA/GSFC Greenbelt Maryland 20771 USA Center for Research and Exploration in Space Science and Technology NASA/GSFC Greenbelt Maryland 20771 USA Center for Mathematics Computation and Cognition UFABC Santo André SP 09210-580 Brazil

Black hole spectroscopy is the proposal to observe multiple quasinormal modes in the ringdown of a binary black hole merger. In addition to the fundamental quadrupolar mode, overtones and higher harmonics may be present and detectable in the gravitational wave signal, allowing for tests of the no-hair theorem. We analyze in detail the strengths and weaknesses of the standard Rayleigh criterion supplied with a Fisher matrix error estimation, and we find that the criterion is useful, but too restrictive. Therefore, we motivate the use of a conservative high Bayes factor threshold to obtain the black hole spectroscopy horizons of current and future detectors; i.e., the distance (averaged in sky location and binary inclination) up to which one or more additional modes can be detected and confidently distinguished from each other. We set up all of our searches for additional modes starting at t=10(M1+M2) after the peak amplitude in simulated signals of circular nonspinning binaries. An agnostic multimode analysis allows us to rank the subdominant modes: for nearly equal mass binaries, we find (ℓ,m,n)=(2,2,1) and (3,3,0) and, for very asymmetric binaries, (3,3,0) and (4,4,0), for the secondary and tertiary modes, respectively. At the current estimated rates for heavy stellar mass binary black hole mergers, with primary masses between 45 and 100 solar masses, we expect an event rate of mergers within our conservative estimate for the (2,2,1) spectroscopy horizon of 0.03–0.10 yr−1 for LIGO at design sensitivity and (0.6−2.4)×103 yr−1 for the future third generation ground-based detector Cosmic Explorer.

关键词： Classical black holes General relativity Gravitational waves

Schrödinger cat states of a nuclear spin qudit in silicon

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arXiv 2024年

作者： Yu, Xi Wilhelm, Benjamin Holmes, Danielle Vaartjes, Arjen Schwienbacher, Daniel Nurizzo, Martin Kringhøj, Anders van Blankenstein, Mark R. Jakob, Alexander M. Gupta, Pragati Hudson, Fay E. Itoh, Kohei M. Murray, Riley J. Blume-Kohout, Robin Ladd, Thaddeus D. Anand, Namit Dzurak, Andrew S. Sanders, Barry C. Jamieson, David N. Morello, Andrea School of Electrical Engineering and Telecommunications UNSW Sydney SydneyNSW2052 Australia Centre for Quantum Computation and Communication Technology Australia School of Physics University of Melbourne MelbourneVIC3010 Australia Institute for Quantum Science and Technology University of Calgary ABT3A 0E1 Canada Diraq Pty. Ltd. SydneyNSW Australia School of Fundamental Science and Technology Keio University Kohoku-ku Yokohama Japan Quantum Performance Laboratory Sandia National Laboratories AlbuquerqueNM87185 United States HRL Laboratories LLC MalibuCA90265-4797 United States NASA Ames Research Center Moffett FieldCA94035 United States KBR Inc. 601 Jefferson St. HoustonTX77002 United States

High-dimensional quantum systems are a valuable resource for quantum information processing. They can be used to encode error-correctable logical qubits, which has been demonstrated using continuous-variable states in microwave cavities or the motional modes of trapped ions. For example, high-dimensional systems can be used to realise ‘Schrödinger cat’ states, superpositions of widely displaced coherent states that can also be used to illustrate quantum effects at large scales. Recent proposals have suggested encoding qubits in high-spin atomic nuclei, finite-dimensional systems that can host hardware-efficient versions of continuous-variable codes. Here we demonstrate the creation and manipulation of Schrodinger cat states using the spin-7/2 nucleus of an antimony atom embedded in a silicon nanoelectronic device. We use a multi-frequency control scheme to produce spin rotations that preserve the symmetry of the qudit, and constitute logical Pauli operations for qubits encoded in the Schrodinger cat states. Our work demonstrates the ability to prepare and control nonclassical resource states, a prerequisite for applications in quantum information processing and quantum error correction using our scalable, manufacturable semiconductor platform. © 2024, CC BY-NC-ND.

关键词： Nanocrystals

Coexistence of Multiple Stacking Charge Density Waves in Kagome Superconductor CsV3Sb5

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arXiv 2022年

作者： Xiao, Qian Lin, Yihao Li, Qizhi Zheng, Xiquan Francoual, Sonia Plueckthun, Christian Xia, Wei Qiu, Qingzheng Zhang, Shilong Guo, Yanfeng Feng, Ji Peng, Yingying International Center for Quantum Materials School of Physics Peking University Beijing100871 China HamburgD-22607 Germany School of Physical Science and Technology ShanghaiTech University Shanghai201210 China ShanghaiTech Laboratory for Topological Physics ShanghaiTech University Shanghai201210 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing100190 China Collaborative Innovation Center of Quantum Matter Beijing100871 China

The recently discovered Kagome family AV3Sb5 (A = K, Rb, Cs) exhibits rich physical phenomena, including non-trivial topological electronic structure, giant anomalous Hall effect, charge density waves (CDW) and superconductivity. Notably, CDW in AV3Sb5 is evidenced to intertwine with its superconductivity and topology, but its nature remains elusive. Here, we combine x-ray scattering experiments and density-functional theory calculations to investigate the CDWs in CsV3Sb5 and demonstrate the coexistence of 2 × 2 × 2 and 2 × 2 × 4 CDW stacking phases. Competition between these CDW phases is revealed by tracking the temperature evolution of CDW intensities, which also manifests in different transition temperatures during warming- and cooling measurements. We also identify a meta-stable quenched state of CsV3Sb5 after fast-cooling process. Our study demonstrates the coexistence of competing CDW stackings in CsV3Sb5, offering new insights in understanding the novel properties of this system. Copyright © 2022, The Authors. All rights reserved.

关键词： Charge density waves

Simulating matrix models with tensor networks

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arXiv 2024年

作者： Brehm, Enrico M. Guo, Yibin Jansen, Karl Rinaldi, Enrico CQTA Deutsches Elektronen-Synchrotron DESY Platanenallee 6 Zeuthen15738 Germany Computation-Based Science and Technology Research Center The Cyprus Institute 20 Kavafi Street Nicosia2121 Cyprus Quantinuum K.K. Otemachi Financial City Grand Cube 3F 1-9-2 Otemachi Chiyoda-ku Tokyo Japan Program RIKEN Saitama Wako351-0198 Japan RIKEN Saitama Wako351-0198 Japan Theoretical Quantum Physics Laboratory Cluster of Pioneering Research RIKEN Wako Saitama351-0198 Japan

Matrix models, as quantum mechanical systems without explicit spatial dependence, provide valuable insights into higher-dimensional gauge and gravitational theories, especially within the framework of string theory, where they can describe quantum black holes via the holographic principle. Simulating these models allows for exploration of their kinematic and dynamic properties, particularly in parameter regimes that are analytically intractable. In this study, we examine the potential of tensor network techniques for such simulations. Specifically, we construct ground states as matrix product states and analyse features such as their entanglement structure. © 2024, CC BY.

关键词： Tensors