Chaos and statistical relaxation in quantum systems of interacting particles
- Felix Izrailev, University of Puebla, Mexico
Tuesday, April 10, 11:00 AM - Theory Seminar
NSCL Seminar Room
Recently, a great deal of attention has been paid to the issue of thermalization in isolated quantum systems, such as many-electron atoms, heavy nuclei and quantum dots. Apart from theoretical aspects, this interest has been triggered by remarkable experimental progresses in the studies of quantum systems with ultracold gases trapped in optical lattices. In this talk we discuss the transition to chaos and the emergence of statistical relaxation in isolated dynamical quantum systems of interacting particles. The approach is based on the concept of delocalization of the eigenstates in the energy shell, controlled by the Gaussian form of the strength function. We show that although the fluctuations of the energy levels in integrable and non-integrable systems are different, global properties of the eigenstates are quite similar, provided the interaction between particles exceeds some critical value. In this case, the statistical relaxation of the systems is comparable, irrespectively of whether they are integrable or not. The numerical data for the quench dynamics manifest excellent agreement with analytical predictions of the theory developed for systems of two-body interactions with a completely random character.