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Seasonal evolution of the englacial and subglacial drainage systems of a temperate glacier revealed by hydrological analysis 被引量:3
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作者 Qiao Liu ShiYin Liu 《Research in Cold and Arid Regions》 2010年第1期51-58,共8页
Englacial and subglacial drainage systems of temperate glaciers have a strong influence on glacier dynamics, glacier-induced floods, glacier-weathering processes, and runoff from glacierized drainage basins. Proglacia... Englacial and subglacial drainage systems of temperate glaciers have a strong influence on glacier dynamics, glacier-induced floods, glacier-weathering processes, and runoff from glacierized drainage basins. Proglacial discharge is partly controlled by the geometry of the glacial drainage network and by the process of producing meltwater. The glacial-drainage system of some alpine glaciers has been characterized using a model based on proglacial discharge analysis. In this paper, we apply cross-correlation analysis to hourly hydro-climatic data collected from China's Hailuogou Glacier, a typical temperate glacier in Mt. Gongga, to study the seasonal status changes of the englacial and subglacial drainage systems by discharge-temperature (Q-T) time lag analy-sis. During early ablation season (April-May) of 2003, 2004 and 2005, the change of englacial and subglacial drainage system usually leads several outburst flood events, which are also substantiated by observing the leakage of supraglacial pond and cre-vasses pond water during field works in April, 2008. At the end of ablation season (October-December), the glacial-drainage net-works become less hydro-efficient. Those events are evidenced by hourly hydro-process near the terminus of Hailuogou Glacier, and the analysis of Q-T time lags also can be a good indicator of those changes. However, more detailed observations or experi-ments, e.g. dye-tracing experiment and recording borehole water level variations, are necessary to describe the evolutionary status and processes of englacial and subglacial drainage systems evolution during ablation season. 展开更多
关键词 glacier drainage system temperate glacier seasonal evolution time lag glacier runoff hydrologic process Hailuogou Glacier
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Time Evolution and Squeezing of Degenerate and Non-degenerate Coupled Parametric Down-Conversion with Driving Term
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作者 LI Jiang-Fan FANG Jia-Yuan XIAO Fu-Liang LIU Xin-Hai WANG Cheng-Zhi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期514-518,共5页
By properly selecting the time-dependent unitary transformation for the linear combination of the number operators, we construct a time-dependent invariant and derive the corresponding auxiliary equations for the dege... By properly selecting the time-dependent unitary transformation for the linear combination of the number operators, we construct a time-dependent invariant and derive the corresponding auxiliary equations for the degenerate and non-degenerate coupled parametric down-conversion system with driving term. By means of this invariant and the Lewis-Riesenfeld quantum invariant theory, we obtain closed formulae of the quantum state and the evolution operator of the system. We show that the time evolution of the quantum system directly leads to production of various generalized one- and two-mode combination squeezed states, and the squeezed effect is independent of the driving term of the Hamiltonian. In some special cases, the current solution can reduce to the results of the previous works. 展开更多
关键词 coupled parametric down-conversion time evolution Lewis-Riesenfeld invariant theory Schrodinger equation squeezed states
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Investigations on the time evolution of the plasma density in argon electron-beam plasma at intermediate pressure
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作者 Xiaoyan BAI Chen CHEN +1 位作者 Hong LI Wandong LIU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第3期47-53,共7页
The time evolution of the argon electron-beam plasma at intermediate pressure and low electron beam intensily was presented.By applying the amplitude modulation with the frequency of 20 Hz on the stable beam current,t... The time evolution of the argon electron-beam plasma at intermediate pressure and low electron beam intensily was presented.By applying the amplitude modulation with the frequency of 20 Hz on the stable beam current,the plasma evolution was studied.A Faraday cup was used for the measurement of the electron beam current and a single electrostatic probe was used for the measurement of the ion current.Experimental results indicated that the ion current was in phase with the electron beam current in the pressure range from 200 Pa to 3000 Pa and in the beam current range lower than 20 mA,the residual density increased approximately linearly with the maximum density in the log-log plot and the fitting coefficient was irrelative to the pressure.And then three kinds of kinetic models were developed and the simulated results given by the kinetic model,without the consideration of the excited atoms,mostly approached to the experimental results.This indicated that the effect of the excited atoms on the plasma density can be ignored at intermediate pressure and low electron beam current intensity,which can greatly simplify the kinetic model.In the end.the decrease of the plasma density when the beam current was suddenly off was studied based on the simplified model and it was found that the decease characteristic at intermediate pressure was approximate to the one at high pressure at low electron beam intensity,which was in good accordance with the experimental results. 展开更多
关键词 electron-beam plasma kinetic model time evolution residual density phase lag
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Time evolution law of a two-mode squeezed light field passing through twin diffusion channels
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作者 Hai-Jun Yu Hong-Yi Fan 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期196-200,共5页
We explore the time evolution law of a two-mode squeezed light field(pure state)passing through twin diffusion channels,and we find that the final state is a squeezed chaotic light field(mixed state)with entanglement,... We explore the time evolution law of a two-mode squeezed light field(pure state)passing through twin diffusion channels,and we find that the final state is a squeezed chaotic light field(mixed state)with entanglement,which shows that even though the two channels are independent of each other,since the two modes of the initial state are entangled with each other,the final state remains entangled.Nevertheless,although the squeezing(entanglement)between the two modes is weakened after the diffusion,it is not completely removed.We also highlight the law of photon number evolution.In the calculation process used in this paper,we make full use of the summation method within the ordered product of operators and the generating function formula for two-variable Hermite polynomials. 展开更多
关键词 two-mode squeezed light field twin diffusion channels time evolution law entanglement
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New approach for obtaining the time-evolution law of a chaotic light field in a damping gaining-process
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作者 龚黎华 周南润 +1 位作者 胡利云 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期31-33,共3页
A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(... A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(t) is derived and the solution of f for the damping and gaining processes are studied separately. Our approach is direct and the result is concise since it is not necessary for us to know the Kraus operators in advance. 展开更多
关键词 chaotic light field damping gaining process time evolution law quantum communication
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Time evolution of negative binomial optical field in a diffusion channel
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作者 刘堂昆 吴盼盼 +2 位作者 单传家 刘继兵 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期97-100,共4页
We find the time evolution law of a negative binomial optical field in a diffusion channel. We reveal that by adjusting the diffusion parameter, the photon number can be controlled. Therefore, the diffusion process ca... We find the time evolution law of a negative binomial optical field in a diffusion channel. We reveal that by adjusting the diffusion parameter, the photon number can be controlled. Therefore, the diffusion process can be considered a quantum controlling scheme through photon addition. 展开更多
关键词 negative binomial optical field time evolution diffusion channel integration within an ordered product(IWOP) of operators
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Evolution and Generation of Dynamics of Two-Mode Squeezed States of Time-Dependent Coupled Boson System
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作者 ZHANG Xue ZHENG Tai-Yu ZHENG Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期955-960,共6页
The system of the Hamiltonian involving a driving part,a single mode part,and a two-mode squeezedone and a two-mode coupled one is discussed using the Lewis-Riesenfeld invariant theory.The time evolution operatoris ob... The system of the Hamiltonian involving a driving part,a single mode part,and a two-mode squeezedone and a two-mode coupled one is discussed using the Lewis-Riesenfeld invariant theory.The time evolution operatoris obtained.When the initial state is a coherent state,the quantum fluctuation of the system is calculated,and it isdependent on the squeezed part and the two-mode coupled part,but not dependent on the driving one. 展开更多
关键词 two-mode squeezed states Lewis Riesenfeld invariant theory time evolution operator
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Time Evolution of Artificial Plasma Cloud in Atmospheric Environment
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作者 陆启明 杨维纮 刘万东 《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第4期2427-2432,共6页
By analyzing the time evolution of artificial plasma cloud in the high altitude of atmospheric environment, we found that there are two zones, an exponential attenuation zone and a linearly attenuating zone, existing ... By analyzing the time evolution of artificial plasma cloud in the high altitude of atmospheric environment, we found that there are two zones, an exponential attenuation zone and a linearly attenuating zone, existing in the spatial distribution of electron density of the artificial plasma clouds. The plasma generator's particle flux density only contributes to the exponential attenuation zone, and has no effect on the linear attenuation zone The average electron density in the linear attenuation zone is about 10-5 of neutral particle density, and can diffuse over a wider area. The conclusion will supply some valuable references to the research of electromagnetic wave and artificial plasma interaction, the plasma invisibleness research of missile and special aerocraft, and the design of artificial plasma source. 展开更多
关键词 artificial plasma time evolution plasma generator
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Restudy on Dark Matter Time-Evolution in the Littlest Higgs Model with T-Parity
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作者 QIAO Qing-Peng TANG Jian LI Xue-Qian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1211-1218,共8页
Following previous study, in the littlest Higgs model (LHM), the heavy photon is supposed to be a possiL dark matter candidate and its relic abundance of the heavy photon is estimated in terms of the Boltzman- Lee-W... Following previous study, in the littlest Higgs model (LHM), the heavy photon is supposed to be a possiL dark matter candidate and its relic abundance of the heavy photon is estimated in terms of the Boltzman- Lee-Weinba time-evolution equation. The effect of the T-parity violation is also considered. Our calculations show that when Higmass MH taken to be 300 GeV and do not considering T-parity violation, only two narrow ranges 133 〈 MAH 〈 135 Ge and 167 〈 MAH〈 169 GeV are tolerable with the current astrophysical observation and if 135 〈 MAH 〈 167 GeV there must at least exist another species of heavy particle contributing to the cold dark matter. As long as the T-pari; can be violated, the heavy photon can decay into regular standard model particles and would affect the dark matt abundance in the universe, we discuss the constraint on the T-parity violation parameter based on the present dat Direct detection prospects are also discussed in some detail. 展开更多
关键词 little Higgs dark matter time evolution
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Time evolutions of scalar field perturbation in Schwarzschild de-Sitter black hole from Einstein-scalar–Gauss–Bonnet theory
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作者 Cheng Xu Zhen-Hao Yang +1 位作者 Xiao-Mei Kuang Rui-Hong Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第1期76-81,共6页
The scalar-free black hole could be unstable against the scalar field perturbation when it is coupled to a Gauss–Bonnet(GB)invariant in a special form.It is known that the tachyonic instability in this scenario is tr... The scalar-free black hole could be unstable against the scalar field perturbation when it is coupled to a Gauss–Bonnet(GB)invariant in a special form.It is known that the tachyonic instability in this scenario is triggered by the sufficiently strong GB coupling.In this paper,we focus on the time domain analysis of massive scalar field perturbation around the Schwarzschild de-Sitter black hole in Einstein-scalar–Gauss–Bonnet gravity.By analyzing the scalar field propagation,we find that the scalar field will finally grow when the GB coupling is large enough.This could lead to the instability of the background black hole.Furthermore,we demonstrate how the mass of the scalar field and the GB coupling strength affect the onset of tachyonic instability. 展开更多
关键词 black hole perturbation scalar-Einstein-Gauss-Bonnet gravity time domain evolution me
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Analytical investigation of the boundary-triggered phase transition dynamics in a cellular automata model with a slow-to-start rule 被引量:1
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作者 贾宁 马寿峰 钟石泉 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期38-43,共6页
Previous studies suggest that there are three different jam phases in the cellular automata automaton model with a slow-to-start rule under open boundaries.In the present paper,the dynamics of each free-flow-jam phase... Previous studies suggest that there are three different jam phases in the cellular automata automaton model with a slow-to-start rule under open boundaries.In the present paper,the dynamics of each free-flow-jam phase transition is studied.By analysing the microscopic behaviour of the traffic flow,we obtain analytical results on the phase transition dynamics.Our results can describe the detailed time evolution of the system during phase transition,while they provide good approximation for the numerical simulation data.These findings can perfectly explain the microscopic mechanism and details of the boundary-triggered phase transition dynamics. 展开更多
关键词 traffic flow boundary-triggered phase transition cellular automata time evolution analytical solution
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Analytical Solution for Single—Mode Time—Dependent Oscillator 被引量:1
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作者 HOUGuang XUXin-Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第5期531-534,共4页
Based on the general theory of time-dependent quantum transformation, we use the 'time evolutionoperator' method to solve the single-mode time-dependent oscillator.
关键词 time-dependent transformation time-dependent oscillator time evolution operator
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Time-resolved measurements of NO2 concentration in pulsed discharges by high-sensitivity cavity ring-down spectroscopy 被引量:1
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作者 吴兴伟 李聪 +2 位作者 冯春雷 王奇 丁洪斌 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第5期80-84,共5页
To describe the complex kinetics of formation and destruction mechanism of nitrogen dioxide(NO2), there is an increasing demand for real-time and in situ analysis of NO2 in the discharge region. Pulsed cavity ring-d... To describe the complex kinetics of formation and destruction mechanism of nitrogen dioxide(NO2), there is an increasing demand for real-time and in situ analysis of NO2 in the discharge region. Pulsed cavity ring-down spectroscopy(CRDS) provides an excellent diagnostic approach. In the present paper, CRDS has been applied in situ for time evolution measurement of NO2 concentration which is rarely investigated in gas discharges. In pulsed direct current discharge of NO2/Ar mixture at a pressure of 500 Pa, a peak voltage of -1300 V and a frequency of 30 Hz, for higher initial NO2 concentration(3.05×10^(14)cm^(-3), 8.88×10^(13)cm^(-3)),the NO2 concentration sharply decreases at the beginning of the discharge afterglow and then becomes almost constant, and the pace of decline increases with pulse duration; however, for lower initial NO2 concentration of 1.69×10^(13)cm^(-3), the NO2 concentration also decreases at the beginning of the discharge afterglow for 200 ns and 1 μs pulse durations, while it slightly increases and then declines for 2 μs pulse duration. Thus, the removal of low-level NO2 could not be promoted by a higher mean energy input. 展开更多
关键词 CRDS ns-pulsed discharge time evolution of NO2 concentration
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NONLINEAR INSTABILITY OF WAVETRAIN UNDER INFLUENCES OF SHEAR CURRENT WITH VARYING VORTICITY AND AIR PRESSURE
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作者 周清甫 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1996年第1期24-38,共15页
Under the assumption of weak shear current with varying vorticity in water and weak air pressure the Zakharov theory is extended to include the effects of vorticity and air pressure on the modulation of water waves. T... Under the assumption of weak shear current with varying vorticity in water and weak air pressure the Zakharov theory is extended to include the effects of vorticity and air pressure on the modulation of water waves. This new equation is used to examine the influence of current and wind on the Benjamin-Feir sideband instability and long-time evolution of wavetrain. As strength of the current increases the bandwidth is found broadened, and the maximum growth rate of sidebands decreased. Periodic solution of sidebands in the presence of current is indicated, which means that shear current does not affect the downshift of wave spectrum peak. Energy input by imposing the air pressure leads to the enhancement of the lower sideband, which is in agreement with the finding of Hara and Mei (1991). 展开更多
关键词 nonlinear instability wavetrain long time evolution Zakhrov equation shear current with varying vorticity
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Damping of displaced chaotic light field in amplitude dissipation channel
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作者 Ke Zhang Lan-Lan Li Hong-Yi Fan 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期161-166,共6页
We explore how a displaced chaotic light (DCL) behaves in an amplitude dissipation channel, and what is its time evolution formula of photon number distribution. With the use of the method of integration within ordere... We explore how a displaced chaotic light (DCL) behaves in an amplitude dissipation channel, and what is its time evolution formula of photon number distribution. With the use of the method of integration within ordered product product of operator (IWOP) and the new binomial theorem involving two-variable Hermite polynomials we obtain the evolution law of DCL in the channel. 展开更多
关键词 displaced chaotic light amplitude dissipation channel time evolution formula IWOP
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Effect of Intrinsic Decoherence of Milburn's Model on Entanglement of Two-Qutrit States
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作者 QIU Liang WANG An-Min MA Xiao-San 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期516-520,共5页
We model of intrinsic analyze the time evolution of entanglement of two-qutrit system within the framework of Milburn's decoherence. The entanglement evolution relies not only on the parameters of system, but also on... We model of intrinsic analyze the time evolution of entanglement of two-qutrit system within the framework of Milburn's decoherence. The entanglement evolution relies not only on the parameters of system, but also on the concrete states either pure or mixed. The linear entropy used to measure the extent to which the intrinsic decoherenee affects quantum states is evaluated. 展开更多
关键词 intrinsic decoherence Milburn's model time evolution of entanglement
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Thermal Energy of Confined Gravitons can Vary Cold Geodesic Curves
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作者 Igor E. Bulyzhenkov 《Journal of Physical Science and Application》 2014年第7期468-474,共7页
Internal energy of real warm bodies can change their kinetic-potential energy balance on Keplerian orbits and relativistic geodesic. Chiral nature of the mass results in chirality of gravitons and their energy confine... Internal energy of real warm bodies can change their kinetic-potential energy balance on Keplerian orbits and relativistic geodesic. Chiral nature of the mass results in chirality of gravitons and their energy confinement within the constant energy charge of a moving thermodynamical body. Zero energy-momentum gravitons provide dissipative self-heating and spiral fall of massive stars on gravitating centers. Computed self-heating of the pulsar PSR B1913+16 quantitatively describes its period decay without an outward emission of metric waves in question. Deviation of warm bodies from geodesic trajectories of cold point matter complies with Einstein's directives toward pure field physics of material space plenum without metric singularities. 展开更多
关键词 Zero particles chiral graviton SELF-HEATING thermal time evolution.
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Casimir Effect via a Generalized Matsubara Formalism
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作者 Adolfo P. C. Malbouisson 《Journal of Applied Mathematics and Physics》 2022年第12期3601-3615,共15页
We investigate the Casimir effect in the context of a nontrivial topology by means of a generalized Matsubara formalism. This is performed in the context of a scalar field in D Euclidean spatial dimensions with d comp... We investigate the Casimir effect in the context of a nontrivial topology by means of a generalized Matsubara formalism. This is performed in the context of a scalar field in D Euclidean spatial dimensions with d compactified dimensions. The procedure gives us the advantage of considering simultaneously spatial constraints and thermal effects. In this sense, the Casimir pressure in a heated system between two infinite planes is obtained and the results are compared with those found in the literature. 展开更多
关键词 CAVITIES Simple Systems Time evolution
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Wobbling Motion in the Even-even Nucleus
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作者 SUN Bowen JI Yingzhi CHEN Qibo 《原子核物理评论》 CAS CSCD 北大核心 2024年第1期200-206,共7页
The recent progresses on the wobbling motion are briefly introduced.So far 17 wobbling candidates have been reported in odd-A and even-even nuclei that spread over A≈100,130,160 and 190 mass regions.The two-quasipart... The recent progresses on the wobbling motion are briefly introduced.So far 17 wobbling candidates have been reported in odd-A and even-even nuclei that spread over A≈100,130,160 and 190 mass regions.The two-quasiparticle configuration wobbling in ^(130)Ba and the wobbling motion in a triaxial rotor are taken as examples in this paper to show the wobbling motion in even-even nuclei.For the ^(130)Ba,the wobbling are investigated based on the combination of the covariant density functional theory(CDFT)and the particle rotor model(PRM).The CDFT provides crucial information on the configuration and deformation parameters of observed bands,serving as input for PRM calculations.The corresponding experimental energy spectra and electromagnetic transition probabilities are reproduced.An analysis of the angular momentum geometry reveals the enhanced stability of transverse wobbling of a two-quasiparticle configuration compared to a single-quasiparticle one.For the triaxial rotor,the time evolution of wobbling motion is explored through the solution of Euler equations.This investigation yields valuable insights into the evolution of orientation angles(φ and θ)and angular momentum components.Notably,the study reveals that low-energy states of a triaxial rotor predominantly exhibit wobbling motion around the intermediate axis.Moreover,an increase in excitation energy corresponds to a prolonged period of intermediate axis wobbling motion.Conversely,a contrasting trend is observed in the case of long axis wobbling,where an increase in excitation energy leads to a decrease in the wobbling period. 展开更多
关键词 wobbling motion even-even nucleus two-quasiparticle time evolution
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Quantitative conditions for time evolution in terms of the von Neumann equation
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作者 WenHua Wang HuaiXin Cao +1 位作者 ZhengLi Chen Lie Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第7期54-60,共7页
The adiabatic theorem describes the time evolution of the pure state and gives an adiabatic approximate solution to the Schrrdinger equation by choosing a single eigenstate of the Hamiltonian as the initial state. In ... The adiabatic theorem describes the time evolution of the pure state and gives an adiabatic approximate solution to the Schrrdinger equation by choosing a single eigenstate of the Hamiltonian as the initial state. In quantum systems, states are divided into pure states (unite vectors) and mixed states (density matrices, i.e., positive operators with trace one). Accordingly, mixed states have their own corresponding time evolution, which is described by the von Neumann equation. In this paper, we discuss the quantitative conditions for the time evolution of mixed states in terms of the von Neumann equation. First, we introduce the definitions for uniformly slowly evolving and δ-uniformly slowly evolving with respect to mixed states, then we present a necessary and sufficient condition for the Hamiltonian of the system to be uniformly slowly evolving and we obtain some upper bounds for the adiabatic approximate error. Lastly, we illustrate our results in an example. 展开更多
关键词 quantitative condition time evolution uniformly slowly evolving δ-uniformly slowly evolving upper bound
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