CENTER FOR APPLIED MATHEMATICS AND THEORETICAL PHYSICS

UNIVERZA V MARIBORU UNIVERSITY OF MARIBOR

KREKOVA 2 SI-2000 MARIBOR SLOVENIA

Phone +(386) (2) 2355 350 and 2355 351 Fax +(386) (2) 2355 360

Robnik@uni-mb.si www.camtp.uni-mb.si

PROF.DR. MARKO ROBNIK, DIRECTOR

15:15-16:00 **Prof.Dr. Peter Križan**, University of Ljubljana, Slovenia
*Belle: recent results and future plans*

16:00-16:45 **Prof.Dr. Tomaž Prosen**, University of Ljubljana, Slovenia
*Non-equilibrium dynamics of open quantum spin chains*

16:45-17:15 Tea and Coffee

17:15-18:00 **Prof.Dr. Keiji Saito**, University of Tokyo, Japan
*Semiclassical approach for universality in quantum chaos with
symmetry crossover: Theory and application*

18:00-18:45 **Dr. Susumu Shinohara**, Max-Planck-Institut, Dresden, Germany
*Ray-wave correspondence in optical microcavities*

**Simpozij se prične v sredo 17. junija 2009 ob 15:15 uri
v seminarski sobi CAMTP, Krekova 2, pritličje desno.
Vljudno vabljeni vsi zainteresirani, tudi
študentje. Povzetki predavanj so v prilogi, in tudi dosegljivi
na www.camtp.uni-mb.si**

Prof.Dr. Marko Robnik

-- Direktor**CAMTP** --

-- Direktor

**ABSTRACTS**

**Prof.Dr. Peter Križan**, University of Ljubljana and
J. Stefan Institute, Slovenia

**Belle: recent results and future plans**

The seminar will present some recent highlights in measurements of rare processes involving the B and D mesons, as carried out by the Belle collaboration. We will also dicuss a not so well-known fact that the most important measurements depend critically on the quantum entanglement. Finally, we will review the motivation and plans for the future Super B factory.

**References**

S.-W. Lin et al. (The Belle collaboration), Difference in direct CP violation between charged and neutral B meson decays, Nature 452, 332 (2008)

M. Staric et al. (The Belle collaboration), Evidence for D0-D0bar Mixing, Phys. Rev. Lett. 98, 211803 (2007)

K. Ikado et al. (The Belle Collaboration), Evidence of the Purely Leptonic Decay B tau nu, Phys. Rev. Lett. 97, 251802 (2006)

**Prof.Dr. Tomaž Prosen**, University of Ljubljana, Slovenia

**Non-equilibrium dynamics of open quantum spin chains**

In this talk we shall discuss normal and anomalous properties of open quantum spin 1/2 chains which are driven far from equilibrium by coupling to thermal or magnetic reservoirs. Possible theoretical approaches will be outlined for exact or efficient numerical solution of quantum master euquations for open quantum many body systems.

We will show that time-dependent density-matrix renormalization group can be adapted for efficient numerical calculation of non-equilibrium steady states, and furthermore that canonical quantization in the Fock space of operators can be used in some cases (like in XY spin chains) to obtain exact analytical solutions.

In the second part of the talk I will present some new exciting physics which has been uncovered by the above mentioned methods, in particular the existence of quantum phase transitions and negative differential resistance of non-equilibrium steady states far from equilibrium.

**Prof.Dr. Keiji Saito**, University of Tokyo, Japan

**Semiclassical Approach for Universality in Quantum Chaos with
Symmetry Crossover: Theory and Application**

We address universality of quantum-classical correspondence of chaos when symmetries change. We first consider the energy level statistics of a classically chaotic system in a weak magnetic field. The generating function of the spectral correlation is calculated by using the semiclassical periodic-orbit theory. Next we try to consider GOE-GSE crossover. In this domain, Random matrix results are not known. We show that semiclassical approach can give new results in this regime. In application, chaotic transport is considered in GOE-GSE crossover regime. This regime is relevant in semiconductor with Rashba-coupling which induces very weak spin-orbit coupling by applied electric field. Then conductance, conductance fluctuation, and shot noise etc, are systematically calculated.

**Dr. Susumu Shinohara**, Max-Planck-Institut für Physik Komplexer Systeme, Dresden, Germany

**Ray-wave correspondence in optical microcavities**

The manifestation of ray chaos in the wave description is a fundamental problem in the field of quantum/wave chaos. One encounters this problem when trying to understand the light emission patterns from optical microcavities. In this talk, I will show that a weighted ray dynamical model that incorporates the light leakage effect at a cavity boundary works very well to reproduce experimentally measured emission patterns, although the model is constructed in a somewhat ad-hoc manner. Also, discussion will be given on the role of multimode lasing in observing good correspondence between experimental and ray-calculated data.

**Reference**: S. Shinohara, T. Fukushima, and T. Harayama, "Light
emission patterns from stadium-shaped semiconductor microcavity
lasers", Phys. Rev. A 77, 033807 (2008).

Janez Kaiser 2009-05-28