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Chinese physics B 2013年第10期 567-570页

作者：郑龙吴小山 Laboratory of solid state Microstructures and department of physics Nanjing University

X-ray absorption spectra(XAS) at Mn K-edge and Fe K-edge in LaMn1-x Fe x O3show that with the increase of Fe substitution the chemical valence of Mn4+decreases,while the chemical valence of Fe3+remains *** distortions,such as the rotating and tilting for oxygen octahedron in the unit cell vary with iron content.A phase transition occurs at the Fe content values of 0.2～*** evolutions of rotation and tilting angle of FeO6/MnO6octahedral may be the vital factors to the structure and *** believe that the spin configuration of Fe3+may vary from the intermediate spin t42g e1g(S = 3/2) to the higher spin t32g e2g(S = 5/2) near the phase transition.

关键词： structural distortion X-ray absorption phase transition

Motion of charged particles in bright squeezed vacuum

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Light(Science & Applications) 2024年第2期13卷 347-353页

作者： Matan Even Tzur Oren Cohen solid state Institute and physics department Technion-Israel Institute of TechnologyHaifa3200003Israel

The motion of laser-driven electrons quivers with an average energy termed pondermotive *** explore electron dynamics driven by bright squeezed vacuum(BSV),finding that BSV induces width oscillations,akin to electron quivering in laser light,with an equivalent ponderomotive *** identify closed and open trajectories of the electronic width that are associated with high harmonic generation and above-threshold ionization,respectively,similarly to trajectories of the electron position when its motion is driven by coherent *** the case of bound electrons,the width oscillations may lead to ionization with noisy sub-cycle *** results are foundational for strong-field and free-electron quantum optics,as they shed light on ionization,high harmonic generation,and nonlinear Compton scattering in BSV.

关键词： structure vacuum ionization

Signature of Superconductivity in Pressurized La_(4)Ni_(3)O_(10)

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Chinese physics Letters 2024年第1期41卷 77-84页

作者：李庆张英杰项浙宁张宇航祝熙宇闻海虎 National Laboratory of solid state Microstructures and department of physics Center for Superconducting Physics and MaterialsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

The discovery of high-temperature superconductivity near 80K in bilayer nickelate La_(3)Ni_(2)O_(7)under high pressures has renewed the exploration of superconducting nickelate in bulk *** extension of superconductivity in other nickelates in a broader family is also ***,we report the experimental observation of superconducting signature in trilayer nickelate La_(4)Ni_(3)O_(10)under high *** using a modified solgel method and post-annealing treatment under high oxygen pressure,we successfully obtained polycrystalline La_(4)Ni_(3)O_(10)samples with different transport behaviors at ambient *** we performed high-pressure electrical resistance measurements on these samples in a diamond-anvil-cell ***,the signature of possible superconducting transition with a maximum transition temperature(T_(c))of about 20K under high pressures is observed,as evidenced by a clear drop of resistance and the suppression of resistance drops under magnetic *** the resistance drop is sample-dependent and relatively small,it appears in all of our measured *** argue that the observed superconducting signal is most likely to originate from the main phase of La_(4)Ni_(3)O_(10).Our findings will motivate the exploration of superconductivity in a broader family of nickelates and shed light on the understanding of the underlying mechanisms of high-T_(c) superconductivity in nickelates.

关键词： materials superconductivity signature

Pion-photon and kaon-photon transition distribution amplitudes in the Nambu–Jona-Lasinio model

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Chinese physics C 2024年第8期48卷 94-103页

作者： Jin-Li Zhang Jun Wu department of Mathematics and physics Nanjing Institute of TechnologyNanjing 211167China National Laboratory of solid state Microstructures Department of PhysicsNanjing UniversityNanjing 210093China

The Nambu–Jona-Lasinio model is utilized to investigate the pion-and kaon-photon leading-twist transition distribution amplitudes using proper time ***,the properties of the vector and axial vector pion-photon transition distribution amplitudes are examined,and the results meet the desired *** study involves sum rule and polynomiality *** vector and axial vector pion-photon transition form factors that are present in theπ^(+)→γe^(+)νprocess are the first Mellin moments of the pion-photon transition distribution *** vector transition form factor originates from the internal structure of hadrons,the axial current can be coupled to a pion,this pion is virtual,and its contribution will be present independently of the external *** kaon transition form factors are *** vector form factor's value at zero momentum transfer is determined by the axial anomaly,while this is not the case for the axial *** vector and axial form factors,as well as the neutral pion vector form factor F_(πγγ)(t),are *** to our findings,the pion axial transition form factor is harder than the vector transition form factor and harder than the electromagnetic form *** also discuss the link betweenπ−γandγ−πtransitions distribution amplitudes.

关键词： transition form factors NJL model transition distribution amplitudes

Mott Gap Filling by Doping Electrons through Depositing One Sub-Monolayer Thin Film of Rb on Ca_(2)CuO_(2)Cl_(2)

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Chinese physics Letters 2024年第5期41卷 90-96页

作者：李寒王朝晖范圣泰李华州杨欢闻海虎 National Laboratory of solid state Microstructures and department of physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Understanding the doping evolution from a Mott insulator to a superconductor probably holds the key to resolve the mystery of unconventional superconductivity in copper oxides. To elucidate the evolution of the electronic state starting from the Mott insulator, we dose the surface of the parent phase Ca_(2)CuO_(2)Cl_(2) by depositing Rb atoms, which are supposed to donate electrons to the CuO_(2) planes underneath. We successfully achieved the Rb sub-monolayer thin films in forming the square lattice. The scanning tunneling microscopy or spectroscopy measurements on the surface show that the Fermi energy is pinned within the Mott gap but close to the edge of the charge transfer band. In addition, an in-gap state appears at the bottom of the upper Hubbard band(UHB), and the Mott gap will be significantly diminished. Combined with the Cl defect and the Rb adatom/cluster results, the electron doping is likely to increase the spectra weight of the UHB for the double occupancy. Our results provide information to understand the electron doping to the parent compound of cuprates.

关键词： doping holds Electron

Supercoiled DNA Minicircles under Double-strand Breaks

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Chinese Journal of Polymer Science 2024年第9期42卷 1353-1359,I0007页

作者： Ye-Peng Qiao Chun-Lai Ren National Laboratory of solid state Microstructures and department of physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China

Understanding how supercoiled DNA releases intramolecular stress is essential for its functional ***,the molecular mechanism underlying the relaxation process remains insufficiently *** we employed MD simulations based on the oxDNA2 model to investigate the relaxation process of a 336-base pair supercoiled minicircular DNA under double-strand breaks with two fixed *** simulations show that the conformational changes in the DNA occur continuously,with intramolecular stress release happening abruptly only when the DNA chain traverses the breakage *** relaxation process is influenced not only by the separation distance between the fixed ends but also their ***,we observe an inhibitory effect on the relaxation characterized by small angles,where short terminal loops impede DNA conformational adjustments,preserving the supercoiled *** findings elucidate the intricate interplay between DNA conformational change,DNA motion and intramolecular stress release,shedding light on the mechanisms governing the relaxation of supercoiled DNA at the molecular level.

关键词： Supercoiled DNA DNA minicircle DNA relaxation oxDNA model MD simulation

Ferromagnetism and insulating behavior with a logarithmic temperature dependence of resistivity in Pb_(10-x)Cux(PO_(4))_(6)O

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Science China(physics,Mechanics & Astronomy) 2024年第1期67卷 106-111页

作者： Yuhang Zhang Cong Liu Xiyu Zhu Hai-Hu Wen Center for Superconducting physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Recent claim of discovering above-room-temperature superconductivity(Tc≈400 K)at ambient pressure in copper doped apatite Pb10(PO_(4))_(6)O has stimulated world-wide enthusiasm and impulse of motion.A lot of follow-up works have been carried out with controversial *** check whether superconductivity is really present or absent in the material,we need samples which should have a rather pure phase of Pb_(10-x)Cux(PO_(4))_(6)*** we report the characterization results from the Pb_(10-x)Cux(PO_(4))_(6)O with a fraction of about 97 wt.%inferred from the fitting to the X-ray diffraction pattern,if assuming Cu2S as the only *** resistivity measurements show that it is a semiconductor characterized roughly by a ln(1/T)temperature dependence in wide temperature region without trace of *** measurements show that it has a general ferromagnetic signal with a weak superparamagnetic *** grains of the sample show clear interactions with a Nb Fe B *** detected Cu concentration is much lower than the expected nominal *** results show the absence of metallicity and superconductivity in Pb_(10-x)Cux(PO_(4))_(6)O at ambient pressure,and suggest the presence of strong correlation effect.

关键词： superconductivity Pb10(PO4)6O ferromagnetic correlation effect

Synthesis of covalent organic framework materials and their application in the field of sensing

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Nano Research 2024年第1期17卷 162-195页

作者： Weiyu Zhang Shiwei Liu Qihua Sun Ning Tian Zhaofeng Wu Xinjiang Key Laboratory of solid-state physics and Devices Urumqi 830046China School of physics Science and Technology Xinjiang UniversityUrumqi 830046China

Covalent organic frameworks(COFs)are an emerging type of porous crystalline polymers formed by combining strong covalent bonds with organic building *** to their large surface area,high intrinsic pore space,good crystallization properties,high stability,and designability of the resultant units,COFs are widely studied and used in the fields of gas adsorption,drug transport,energy storage,photoelectric catalysis,electrochemistry,and *** recent years,the rapid development of the Internet of Things and people’s yearning for a better life have put forward higher and more requirements for sensors,which are the core components of the Internet of ***,this paper reviews the recent progress of COFs in synthesis methods and sensing applications,especially in the last five *** paper first introduces structure,properties,and synthesis methods of COFs and discusses advantages and disadvantages of different synthesis ***,the research progress of COFs in different sensing fields,such as metal ion sensors,gas sensors,biomedical sensors,humidity sensors,and pH sensors,is introduced *** and prospects are also presented in order to provide a reference for researchers concerned with COFs and sensors.

关键词： covalent organic framework materials structural design and synthesis sensing application gas sensors

Pressure-induced color change arising from transformation between intra-and inter-band transitions in LuH_(2±x)N_(y)

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Science China(physics,Mechanics & Astronomy) 2024年第2期67卷 161-166页

作者： Zhe Liu Yingjie Zhang Shenyang Huang Xue Ming Qing Li Chenghao Pan Yaomin Dai Xiaoxiang Zhou Xiyu Zhu Hugen Yan Hai-Hu Wen Center for Superconducting physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China state Key Laboratory of Surface physics Key Laboratory of Micro and Nano-Photonic Structures of the Ministry of EducationDepartment of PhysicsFudan UniversityShanghai 200433China

The pressure-induced color change in the nitrogen-doped lutetium hydride has triggered extensive discussions about the underlying physics and potential ***,we study the optical response of LuH_(2±x)N_(y)in a broad frequency range at ambient pressure and its evolution with pressure in the visible spectral *** broad-band optical spectra at ambient pressure reveal a Drude component associated with intra-band electronic transitions and two Lorentz components(L1 and L2)arising from inter-band electronic *** application of pressure causes a spectral weight transfer from L1 to the Drude component,leading to a blue shift of the plasma edge in the reflectivity spectrum alongside a reduction of the high-frequency *** results suggest that the pressure-induced color change in LuH_(2±x)N_(y)is closely related to the transformation between intra-and inter-band electronic transitions,providing new insights into the mechanism of the pressure-induced color change in LuH_(2±x)N_(y).

关键词： nitrogen-doped lutetium hydride optical spectroscopy high-pressure technique color change

Machine-learning-assisted efficient reconstruction of the quantum states generated from the Sagnac polarization-entangled photon source

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Chinese physics B 2024年第8期33卷 50-54页

作者：毛梦辉周唯李新慧杨然龚彦晓祝世宁 National Laboratory of solid state Microstructures and School of physics Nanjing UniversityNanjing 210093China Author notes

Neural networks are becoming ubiquitous in various areas of physics as a successful machine learning(ML)technique for addressing different *** on ML technique,we propose and experimentally demonstrate an efficient method for state reconstruction of the widely used Sagnac polarization-entangled photon *** properly modeling the target states,a multi-output fully connected neural network is well trained using only six of the sixteen measurement bases in standard tomography technique,and hence our method reduces the resource consumption without loss of *** demonstrate the ability of the neural network to predict state parameters with a high precision by using both simulated and experimental ***,the mean absolute error for all the parameters is below 0.05 for the simulated data and a mean fidelity of 0.99 is achieved for experimentally generated *** method could be generalized to estimate other kinds of states,as well as other quantum information tasks.

关键词： machine learning state estimation quantum state tomography polarization-entangled photon source