Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ergodic properties of a generic non-integrable quantum many-body system
  in thermodynamic limit   We study a generic but simple non-integrable quantum {\em many-body} system
of {\em locally} interacting particles, namely a kicked $t-V$ model of spinless
fermions on 1-dim lattice (equivalent to a kicked Heisenberg XX-Z chain of 1/2
spins). Statistical properties of dynamics (quantum ergodicity and quantum
mixing) and the nature of quantum transport in {\em thermodynamic limit} are
considered as the kick parameters (which control the degree of
non-integrability) are varied. We find and demonstrate {\em ballistic}
transport and non-ergodic, non-mixing dynamics (implying infinite conductivity
at all temperatures) in the {\em integrable} regime of zero or very small kick
parameters, and more generally and important, also in {\em non-integrable}
regime of {\em intermediate} values of kicked parameters, whereas only for
sufficiently large kick parameters we recover quantum ergodicity and mixing
implying normal (diffusive) transport. We propose an order parameter (charge
stiffness $D$) which controls the phase transition from non-mixing/non-ergodic
dynamics (ordered phase, $D>0$) to mixing/ergodic dynamics (disordered phase,
D=0) in the thermodynamic limit. Furthermore, we find {\em exponential decay of
time-correlation function} in the regime of mixing dynamics.
  The results are obtained consistently within three different numerical and
analytical approaches: (i) time evolution of a finite system and direct
computation of time correlation functions, (ii) full diagonalization of finite
systems and statistical analysis of stationary data, and (iii) algebraic
construction of quantum invariants of motion of an infinite system, in
particular the time averaged observables.

3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math