Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Chinese Physics Letters

Evolution of Spin and Charge in a System with Interacting Impurity and Conducting Electrons

Zhang Yong-Mei, Shi‐Jie Xiong

Published Nov 1, 2003• 6 citations
Publisher

Abstract

We investigate the dynamics of spin and charge in an interacting system consisting of impurity and conducting electrons. The time evolution of spin and charge in the impurity is given by solving the time-dependent Schrödinger equations for the many-body states of the interacting system. By switching on the interaction between impurity and conducting electrons, the spin and charge of the impurity begin oscillations with frequencies that reflect the elementary excitations of the interacting system. The dynamics reflects the basic picture of the Kondo effect.

DOI
10.1088/0256-307x/20/11/034

Related papers

Evolution of Spin and Charge in a System with Interacting Impurity and Conducting Electrons

张永梅, 熊诗杰

We investigate the dynamics of spin and charge in an interacting system consisting of impurity and conduct-ing electrons. The time evolution of spin and charge in the impurity is given by solving the time-dependent Schroedinger equations for the many-body states of the interacting system. By switching on the interaction be-tween impurity and conducting electrons, the spin and charge of the impurity begin oscillations with frequencies that reflect the elementary excitations of the interacting system. The dynamics reflects the basic picture of the Kondo effect.

Chinese Physics Letters•Jan 1, 2003•0 citations

Spin- and charge-density oscillations in spin chains and quantum wires

Stefan Rommer, Sebastian Eggert

We analyze the spin- and charge-density oscillations near impurities in spin chains and quantum wires. These so-called Friedel oscillations give detailed information about the impurity and also about the interactions in the system. The temperature dependence of these oscillations explicitly shows the renormalization of backscattering and conductivity, which we analyze for a number of different impurity models. We are also able to analyze screening effects in one dimension. The relation to the Kondo effect and experimental consequences are discussed.

arXiv:cond-mat/0002001•Physical review. B, Condensed matter•Aug 15, 2000•60 citations

Spin and charge oscillations of a dot due to interaction with itinerant electrons

Yong-Jian Xiong, Shi‐Jie Xiong

We study the spin and charge oscillations of a quantum dot by exactly solving the time-dependent many-body Schr\"odinger equation of a system with a dot embedded in a ring. The dot is characterized by the on-site Coulomb interaction and the gate voltage that governs the occupation status. The itinerant electrons are moving in the ring. By switching on the coupling between the dot and the ring the spin and charge on the dot begin to have undamped oscillations. In the regime of single occupation of the dot, there exists a base frequency of the oscillations that is associated with the spin excitations. Some higher frequencies may be associated with both the charge and spin motions. The results reveal the dynamical characteristics of the spin and charge degrees of freedom and the spectrum of low-energy excitations.

Physical review. B, Condensed matter•Jun 12, 2001•5 citations

Quench dynamics of the Kondo effect: Transport across an impurity coupled to interacting wires

Moallison F. Cavalcante, Rodrigo G. Pereira, Maria C. O. Aguiar

We study the real-time dynamics of the Kondo effect after a quantum quench in which a magnetic impurity is coupled to two metallic Hubbard chains. Using an effective field theory approach, we find that for noninteracting electrons the charge current across the impurity is given by a scaling function that involves the Kondo time. In the interacting case, we show that the Kondo time decreases with the strength of the repulsive interaction and the time dependence of the current reveals signatures of the Kondo effect in a Luttinger liquid. In addition, we verify that the relaxation of the impurity magnetization does not exhibit universal scaling behavior in the perturbative regime below the Kondo time. Our results highlight the role of nonequilibrium dynamics as a valuable tool in the study of quantum impurities in interacting systems.

arXiv:2211.02444•Physical review. B./Physical review. B•Feb 6, 2023•4 citations

Spin precession and real-time dynamics in the Kondo model: Time-dependent numerical renormalization-group study

Frithjof B. Anders, Avraham Schiller

A detailed derivation of the recently proposed time-dependent numerical renormalization-group (TD-NRG) approach to nonequilibrium dynamics in quantum-impurity systems is presented. We demonstrate that the method is suitable for fermionic as well as bosonic baths. Comparisons with exact analytical results for the charge relaxation in the resonant-level model and for dephasing in the spin-boson model establish the accuracy of the method. The real-time dynamics of a single spin coupled to each type of bath is investigated. We use the TD-NRG to calculate the spin relaxation and spin precession of a single Kondo impurity. The short- and long-time dynamics are studied as a function of temperature in the ferromagnetic and antiferromagnetic regimes. The short-time dynamics agrees very well with analytical results obtained at second order in the exchange coupling $J$. In the ferromagnetic regime, the transient spin decay is described by the scaling variable $x=2{\ensuremath{\rho}}_{F}\ensuremath{\mid}J(T)\ensuremath{\mid}Tt$. In the antiferromagnetic regime, the long-time decay is governed for $T<{T}_{K}$ by the Kondo time scale $1∕{T}_{K}$. Here ${\ensuremath{\rho}}_{F}$ is the conduction-electron density of states, ${T}_{K}$ is the Kondo temperature, and $J(T)$ is the effective exchange coupling at temperature $T$. Results for spin precession are obtained by rotating the external magnetic field from the $x$ axis to the $z$ axis.

arXiv:cond-mat/0604517•Physical Review B•Dec 18, 2006•250 citations

Time-dependent transport through quantum-impurity systems with Kondo resonance

YongXi Cheng, WenJie Hou, YuanDong Wang +3 more

We investigate the time-dependent transport properties of single and double quantum-impurity systems based on the hierarchical equations of motion (HEOM) approach. In the Kondo regime, the dynamical current oscillates with time in both cases due to the temporal coherence of electrons tunneling through the device, which shares the same mechanism as the single-level resonance without e–e interactions, but shows some different characteristics. For single quantum-impurity systems, the temperature T has an inhibitory effect on the oscillations of dynamic current through its suppression of the Kondo effects. The amplitude of the current oscillations is attenuated by the e–e interaction U in the Kondo regime. The frequency of the current oscillations is found almost independent of T and U . For parallel-coupling double quantum-impurity systems, the oscillation of the current shows similar behavior to the single one, but with two-to-three times larger amplitudes. At the limit of small inter-impurity coupling the oscillation of the current exhibits enhanced characters, while it is weakened at the other limit.

arXiv:1410.1235•New Journal of Physics•Mar 3, 2015•37 citations
We investigate the dynamics of spin and charge in an interacting system consisting of impurity and conducting electrons. The time evolution of spin and charge in the impurity is given by solving the time-dependent Schrödinger equations for the many-body states of the interacting system. By switching on the interaction between impurity and conducting electrons, the spin and charge of the impurity begin oscillations with frequencies that reflect the elementary excitations of the interacting system. The dynamics reflects the basic picture of the Kondo effect.
We investigate the dynamics of spin and charge in an interacting system consisting of impurity and conduct-ing electrons. The time evolution of spin and charge in the impurity is given by solving the time-dependent Schroedinger equations for the many-body states of the interacting system. By switching on the interaction be-tween impurity and conducting electrons, the spin and charge of the impurity begin oscillations with frequencies that reflect the elementary excitations of the interacting system. The dynamics reflects the basic picture of the Kondo effect.
We analyze the spin- and charge-density oscillations near impurities in spin chains and quantum wires. These so-called Friedel oscillations give detailed information about the impurity and also about the interactions in the system. The temperature dependence of these oscillations explicitly shows the renormalization of backscattering and conductivity, which we analyze for a number of different impurity models. We are also able to analyze screening effects in one dimension. The relation to the Kondo effect and experimental consequences are discussed.
We study the spin and charge oscillations of a quantum dot by exactly solving the time-dependent many-body Schr\"odinger equation of a system with a dot embedded in a ring. The dot is characterized by the on-site Coulomb interaction and the gate voltage that governs the occupation status. The itinerant electrons are moving in the ring. By switching on the coupling between the dot and the ring the spin and charge on the dot begin to have undamped oscillations. In the regime of single occupation of the dot, there exists a base frequency of the oscillations that is associated with the spin excitations. Some higher frequencies may be associated with both the charge and spin motions. The results reveal the dynamical characteristics of the spin and charge degrees of freedom and the spectrum of low-energy excitations.
We study the real-time dynamics of the Kondo effect after a quantum quench in which a magnetic impurity is coupled to two metallic Hubbard chains. Using an effective field theory approach, we find that for noninteracting electrons the charge current across the impurity is given by a scaling function that involves the Kondo time. In the interacting case, we show that the Kondo time decreases with the strength of the repulsive interaction and the time dependence of the current reveals signatures of the Kondo effect in a Luttinger liquid. In addition, we verify that the relaxation of the impurity magnetization does not exhibit universal scaling behavior in the perturbative regime below the Kondo time. Our results highlight the role of nonequilibrium dynamics as a valuable tool in the study of quantum impurities in interacting systems.
A detailed derivation of the recently proposed time-dependent numerical renormalization-group (TD-NRG) approach to nonequilibrium dynamics in quantum-impurity systems is presented. We demonstrate that the method is suitable for fermionic as well as bosonic baths. Comparisons with exact analytical results for the charge relaxation in the resonant-level model and for dephasing in the spin-boson model establish the accuracy of the method. The real-time dynamics of a single spin coupled to each type of bath is investigated. We use the TD-NRG to calculate the spin relaxation and spin precession of a single Kondo impurity. The short- and long-time dynamics are studied as a function of temperature in the ferromagnetic and antiferromagnetic regimes. The short-time dynamics agrees very well with analytical results obtained at second order in the exchange coupling JJJ. In the ferromagnetic regime, the transient spin decay is described by the scaling variable $x=2{\ensuremath{\rho}}_{F}\ensuremath{\mid}J(T)\ensuremath{\mid}Tt$. In the antiferromagnetic regime, the long-time decay is governed for T<TKT<{T}_{K}T<TK​ by the Kondo time scale 1∕TK1∕{T}_{K}1∕TK​. Here ${\ensuremath{\rho}}_{F}$ is the conduction-electron density of states, TK{T}_{K}TK​ is the Kondo temperature, and J(T)J(T)J(T) is the effective exchange coupling at temperature TTT. Results for spin precession are obtained by rotating the external magnetic field from the xxx axis to the zzz axis.
We investigate the time-dependent transport properties of single and double quantum-impurity systems based on the hierarchical equations of motion (HEOM) approach. In the Kondo regime, the dynamical current oscillates with time in both cases due to the temporal coherence of electrons tunneling through the device, which shares the same mechanism as the single-level resonance without e–e interactions, but shows some different characteristics. For single quantum-impurity systems, the temperature T has an inhibitory effect on the oscillations of dynamic current through its suppression of the Kondo effects. The amplitude of the current oscillations is attenuated by the e–e interaction U in the Kondo regime. The frequency of the current oscillations is found almost independent of T and U . For parallel-coupling double quantum-impurity systems, the oscillation of the current shows similar behavior to the single one, but with two-to-three times larger amplitudes. At the limit of small inter-impurity coupling the oscillation of the current exhibits enhanced characters, while it is weakened at the other limit.