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Chinese physics B 2024年第7期33卷 448-454页

作者：潘小龙王豪柳雷陈向荣耿华运 college of physics Sichuan UniversityChengdu 610065China National Key Laboratory of Shock Wave and Detonation physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China HEDPS Center for Applied Physics and Technologyand College of EngineeringPeking UniversityBeijing 100871China

Mn_(3)TeO_(6)(MTO) has been experimentally found to adopt a P2_(1)/In structure under high pressure,which exhibits a significantly smaller band gap compared to the atmospheric R3 *** this study,we systematically investigate the magnetism,structural phase transition,and electronic properties of MTO under high pressure through first-principles *** R3 and P2_(1)/n phases of MTO are antiferromagnetic at zero *** R3 phase transforms to the P2_(1)/n phase at 7.5 8 GPa,accompanied by a considerable volume collapse of about 6.47%.Employing the accurate method that combines DFT+U/and GW,the calculated band gap of R3 phase at zero pressure is very close to the experimental values,while that of the P2_(1)/n phase is significantly *** main reason for this difference is that the experimental study incorrectly used the Kubelka-Munk plot for the indirect band gap to obtain the band gap of the P2_(1)/n phase instead of the Kubelka-Munk plot for the direct band ***,our study reveals that the transition from the R3 phase to the P2_(1)/n phase is accompanied by a slight reduction in the band gap.

关键词： magnetism phase transition band gap high pressure

Kármán vortex street in a spin–orbit-coupled Bose–Einstein condensate with PT symmetry

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Chinese physics B 2024年第6期33卷 289-296页

作者：邵凯花席保龙席忠红涂朴王青青马金萍赵茜石玉仁 college of physics and Electronic engineering Northwest Normal UniversityLanzhou 730070China college of physics and Hydropower engineering Gansu Normal College For NationalitiesHezuo 747000China college of Intelligent Manufacturing Sichuan University of Arts and ScienceDazhou 635000China

The dynamics of spin–orbit-coupled Bose–Einstein condensate with parity-time symmetry through a moving obstacle potential is simulated numerically. In the miscible two-component condensate, the formation of the Kármán vortex street is observed in one component, while ‘the half-quantum vortex street' is observed in the other component. Other patterns of vortex shedding, such as oblique vortex dipoles, V-shaped vortex pairs, irregular turbulence, and combined modes of various wakes, can also be found. The ratio of inter-vortex spacing in one row to the distance between vortex rows is approximately0.18, which is less than the stability condition 0.28 of classical fluid. The drag force acting on the obstacle potential is simulated. The parametric regions of Kármán vortex street and other vortex patterns are calculated. The range of Kármán vortex street is surrounded by the region of combined modes. In addition, spin–orbit coupling disrupts the symmetry of the system and the gain-loss affects the local particle distribution of the system, which leads to the local symmetry breaking of the system, and finally influences the stability of the Kármán vortex street. Finally, we propose an experimental protocol to realize the Kármán vortex street in a system.

关键词： Kármán vortex street Bose–Einstein condensate spin–orbit-coupled parity-time symmetry

Coherence of nonlinear Bloch dynamics of Bose-Einstein condensates in deep optical lattices

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Chinese physics B 2024年第4期33卷 297-303页

作者：张爱霞张薇王杰胡潇文米来来薛具奎 college of physics and Electronics engineering Northwest Normal UniversityLanzhou 730070China

Atomic interaction leads to dephasing and damping of Bloch oscillations(BOs)in optical lattices,which limits observation and applications of *** to obtain persistent BOs is particularly ***,the nonlinear Bloch dynamics of the Bose-Einstein condensate with two-body and three-body interactions in deep optical lattices is *** damping rate induced by interactions is *** damping induced by two-body interaction plays a dominant role,while the damping induced by three-body interaction is ***,when the two-body and three-body interactions satisfy a threshold,long-lived coherent BOs are ***,the Bloch dynamics with periodical modulation of linear force is *** frequencies of linear force corresponding to resonance and pseudoresonance are obtained,and rich dynamical phenomena,i.e.,stable and strong BOs,drifting and dispersion of wave packet,are *** controllable Bloch dynamics is provided with the periodic modulation of the linear force.

关键词： Bose-Einstein condensate atomic interaction Bloch oscillations

Differences between two methods to derive a nonlinear Schrödinger equation and their application scopes

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Chinese physics B 2024年第2期33卷 421-429页

作者：陈羽西张恒段文山 college of physics and Electronic engineering Northwest Normal UniversityLanzhou 730070China

The present paper chooses a dusty plasma as an example to numerically and analytically study the differences between two different methods of obtaining nonlinear Schrödinger equation(NLSE).The first method is to derive a Korteweg–de Vries(KdV)-type equation and then derive the NLSE from the KdV-type equation,while the second one is to directly derive the NLSE from the original *** is found that the envelope waves from the two methods have different dispersion relations,different group *** results indicate that two envelope wave solutions from two different methods are completely *** results also show that the application scope of the envelope wave obtained from the second method is wider than that of the first one,though both methods are valuable in the range of their corresponding application *** is suggested that,for other systems,both methods to derive NLSE may be correct,but their nonlinear wave solutions are different and their application scopes are also different.

关键词： dusty plasmas nonlinear waves particle-in-cell simulation

One-Dimensional Modulational Instability of Broad Optical Beams In Photorefractive Crystals with Both Linear and Quadratic Electro-Optic Effects

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激光与光电子学进展 2024年第5期61卷 397-403页

作者： Hao Lili Wang Zhen Tang Hongxia Zhang Xiaoyang Yang Qi Wang Qiang Department of physics College of physics and Electronic EngineeringNortheast Petroleum UniversityDaqing 163318HeilongjiangChina Department of physics College of Electrical EngineeringSuihua UniversitySuihua 152000HeilongjiangChina

We present a theoretical study of the one-dimensional modulational instability of a broad optical beam propagating in a biased photorefractive crystal with both linear and quadratic electro-optic effects(Kerr effect)under steadystate ***-dimensional modulational instability growth rates are obtained by treating the space-charge field equation globally and *** theoretical reasoning and numerical simulation show that both the global and local modulational instability gains are governed simultaneously by the strength and the polarity of external bias field and by the ratio of the intensity of the broad beam to that of the dark *** a strong bias field,the results obtained using these two methods are in good agreement in the low spatial frequency ***,the instability growth rate increases with the bias field,and the maximum instability growth occurs when ratio of light intensity to dark irradiance is 0.88.

关键词： nonlinear optics photorefractive effects spatial soliton modulational instability

Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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Science China(Technological Sciences) 2024年第5期67卷 1297-1316页

作者： CHEN Jie GUO RuiLong GUO HengYu college of physics and Electronic engineering Chongqing Normal UniversityChongqing 401331China Department of Applied physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies

Reconstructing coherent dynamics of bound states induced by strong attosecond XUV pulses

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Chinese Optics Letters 2024年第2期22卷 56-63页

作者：贾利娟刘明清王新强徐龙闫培光姜维超傅立斌 Institute of Quantum Precision Measurement College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Department of physics Xiamen UniversityXiamen 361005China Graduate School of China Academy of engineering physics Beijing 100193China

We propose a scheme that utilizes weak-field-induced quantum beats to investigate the electronic coherences of atoms driven by a strong attosecond extreme ultraviolet(XUV)*** technique involves using a strong XUV pump pulse to excite and ionize atoms and a time-delayed weak short pulse to probe the photoelectron *** theoretical analysis demonstrates that the information regarding the bound states,initiated by the strong pump pulse,can be precisely reconstructed from the weak-field-induced quantum beat *** examine this scheme,we apply it to the attosecond XUV laser-induced ionization of hydrogen atoms by solving a three-dimensional time-dependent Schr?dinger *** work provides an essential reference for reconstructing the ultrafast dynamics of bound states induced by strong XUV attosecond pulses.

关键词： attosecond pulse bound-state dynamics quantum beats

Theoretical investigation of electron-impact ionization of W8+ion

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Chinese physics B 2024年第3期33卷 341-349页

作者：张世平张芳军张登红丁晓彬蒋军颉录有马玉龙李麦娟 Marek Sikorski 董晨钟 Key Laboratory of Atomic and Molecular physics & Functional Materials of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070China

The electron-impact single ionization cross section for W8+ion has been calculated using flexible atomic code,employing the level-to-level distorted-wave *** calculations takes into account contributions form both direct ionization(DI)and excitation autoionization(EA).However,the theoretical predictions,based solely on the ground state,tends to underestimate the experimental *** discrepancy can be mitigated by incorporation contributions from excited *** extended the theoretical analysis,including the contributions from the long-lived metastable states with lifetimes exceeding 1.5×10-5 *** employed two statistical models to predict the fraction of ground state ions in the parent ion *** a 79%fraction of parent ions in ground configuration,the experiment measurements align with the *** we derived the theoretical cross-section for the ground state as correlated plasma rate coefficients,and compared it with existing *** the uncertainty in our calculations,our results are still acceptable.

关键词： tungsten ions electron-impact ionization cross section

Cr-induced fusion reactions to synthesize superheavy elements

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Nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.Madhu H.C.Manjunatha N.Sowmya B.M.Rajesh L.Seenappa R.S.Susheela Department of physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of physics Government First Grade CollegeMulbagalKarnataka 563131India Department of physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)Cr+^(243)Am,23.2 fb at 236 MeV for ^(54)Cr+^(247)Cm,95.6 fb at 240 MeV for ^(53)Cr+248Bk,and 1.33 fb at 242 MeV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections

Optimizing electronic structure of Mo_(2)TiC_(2)T_(x)MXene through Nb doping for enhanced electrochemical performance

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Nano Research 2024年第8期17卷 7174-7181页

作者： Jingyuan Zhao Wenzheng Yan Zhaoxi Liu Xiaobin Liu Yapeng Tian Xinwei Cui Henan Institute of Advanced Technology College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450003China college of physics and Electronic Information engineering Guilin University of TechnologyGuilin 514004China

MXene is a promising electrode material for both high volumetric capacitance and high-rate performance in ***,the current study has mainly focused on the monometallic element Ti_(3)C_(2)T_(x)MXene until now,while the bimetallic and multimetallic MXene have received comparatively less *** this work,we demonstrate that the electronic structure of the Mo_(2)TiC_(2)T_(x)MXene could be regulated by fine-tuning the content of doped Nb *** enhanced electron cloud density of surface–O termination and the electron spin of the Mo atoms in the Mo_(2)TiC_(2)T_(x)MXene,leads to the boost of electric double-layer capacitor(EDLC)and improvement of *** a consequence,the electrochemical performance of Nb-doped Mo_(2)TiC_(2)T_(x)MXene(Nb-0.3-MXene)demonstrates a capacitance of 398 F·cm^(−3),roughly doubling that of the pristine Mo_(2)TiC_(2)T_(x)MXene electrode at 197 F·cm^(−3)in the 3 M H_(2)SO_(4)*** the same time,the Nb-0.3-MXene could even maintain a capacitance of 82.75%at 200 mV·s−1,with high cyclic stability for 19,000 cycles at 10 A·g−***,Nb-0.3-MXene-based hybrid supercapacitors deliver a remarkable volumetric energy density of 48.1 W·h·L^(−1)at 230.7 W·L^(−1),and 34.4 W·h·L^(−1)at a high power density of 82.6 kW·L^(−1).There exists a balance between the volumetric capacitance and rate performance with different ratios of Nb atoms in the Nb-doped MXene due to the strong interaction between the Nb-doped MXene and the intercalated ***,optimizing the electronic structure of MXene through heteroatom doping is of great potential for enhanced supercapacitor performance.

关键词： niobium doping electronic structure Mo_(2)TiC_(2)T_(x)MXene electron spin rate performance volumetric capacitance