Transient carrier dynamics in a Mott insulator with antiferromagnetic order

Abstract

We study transient dynamics of hole carriers injected at a certain time into a Mott insulator with antiferromagnetic long range order. This is termed "dynamical hole doping" as contrast with chemical hole doping. Theoretical framework for the transient carrier dynamics are presented based on the two dimensional t− J model. Time dependences of the optical conductivity spectra as well as the one-particle excitation spectra are calculated based on the Keldysh Green's function formalism at zero temperature combined with the self-consistent Born approximation. At early stage after dynamical hole doping, the Drude component appears, and then incoherent components originating from hole-magnon scatterings start to grow. Fast oscillatory behavior due to coherent magnon, and slow relaxation dynamics are confirmed in the spectra. Time profiles are interpreted as that doped bare holes are dressed by magnon clouds, and are relaxed into spin polaron quasi-particle states. Characteristic relaxation times for Drude and incoherent peaks strongly depend on momentum of a dynamically doped hole, and the exchange constant. Implications to the recent pump-probe experiments are discussed. PACS numbers:

Photoinduced correlated electron dynamics in a two-leg ladder Hubbard system

“…Quasi one-and two-dimensional cuprate oxides 7,10,11,[15][16][17][18][19] , halogen-bridged complexes 8,12 and BEDT-TTF molecular solids 13,14 are the examples. This is attributed to a rich variety of equilibrium states and the simple lattice structures.…”

Biexciton in one-dimensional Mott insulators

“…The growing interest in the ultrafast dynamics of correlated electron systems synchronizes to the development of a new field called 'non-equilibrium quantum physics in solids'. In fact, new theoretical approaches have recently been explored to analyse the charge, spin, and lattice dynamics of non-equilibrium states after photoirradiation, as exemplified by the dynamical mean field theory 19 and the time-dependent density-matrix renormalization group method 20,21 .In the non-equilibrium quantum physics of correlated electron systems, the charge dynamics of photoexcited Mott insulators is the most fundamental subject to be studied from both the experimental 6,12,16-18 and theoretical viewpoints [22][23][24][25][26][27][28] . Recent studies have focussed on Mott insulator states realized not only in solids such as transition metal compounds 6,16-18 and organic molecular materials 12 but also in ultra-cold atoms on an optical lattice 29,30,31 .…”

Time Evolution of the Kondo Resonance in Response to a Quench

“…In the latter, further progress hinges on an accurate non-perturbative solution for the nonequilibrium Green functions of an effective quantum impurity model. Such a solution, beyond allowing timeresolved spectroscopies of correlated lattice systems within DMFT to be addressed [43][44][45][46][47], would also be useful in understanding time-resolved scanning tunnelling microscopy of nanoscale systems [48] and proposed cold atom realizations of Kondo correlated states [49][50][51][52], which could be probed with real-time radio-frequency spectroscopy [53][54][55].In this Letter, we use the time-dependent numerical renormalization group (TDNRG) approach [56][57][58][59][60][61][62] to calculate the retarded two-time Green function, G(t 1 = t + t , t 2 = t), and associated spectral function, A(ω, t), of the Anderson impurity model in response to a quench at time t = 0, and apply this to investigate in detail the time evolution of the Kondo resonance. This topic has been addressed before within several approaches, including the non-crossing approximation [26,63], conserving approximations [64] and within CTQMC for quantum dots out of equilibrium [32].…”

“…In the latter, further progress hinges on an accurate non-perturbative solution for the nonequilibrium Green functions of an effective quantum impurity model. Such a solution, beyond allowing timeresolved spectroscopies of correlated lattice systems within DMFT to be addressed [43][44][45][46][47], would also be useful in understanding time-resolved scanning tunnelling microscopy of nanoscale systems [48] and proposed cold atom realizations of Kondo correlated states [49][50][51][52], which could be probed with real-time radio-frequency spectroscopy [53][54][55].…”