ELFT HÍRADÓ

[Szeminarium koordinator <szfi-seminar AT wigner.mta.hu>]

VAJNA SZABOLCS (BME Fizika tanszék, vendéglátó: Asbóth János):
"Topological classification of dynamical phase transitions"

Idõpont: 2014. október 28. (kedd) 10:00
Hely: MTA Wigner FK SZFI, I. épület 1. emeleti Tanácsterem
       
Részletes információ (tartalmi kivonat):
    <p>Dynamical phase transitions (DPT) are non-equilibrium phenomena 
occurring in systems following a quantum quench, and are characterized by 
nonanalytical time evolution of the dynamical free energy. First I introduce 
DPTs in the context of spin chains wtih particular focus on the quantum XY 
chain. Afterwards I generalize the problem for general 2-band systems in one 
and two dimensions (eg. SSH model, Kitaev-chain, Haldane model, p+ip 
superconductor, etc.), where we showed that the time evolution of the 
dynamical free energy is crucially affected by the ground state topology of 
both the initial and final Hamiltonians, implying DPTs when the topology is 
changed under the quench. The singularities of dynamical free energy in the 
2D case are qualitatively different from those of the 1D case, the cusps 
appear only in the first time derivative.</p>


Minden érdeklõdõt szívesen látunk!