Dóra Balázs - Loschmidt echo in Luttinger liquids


(MTA Wigner FK SZFI, vendéglátó: Legeza Örs)

"Loschmidt echo in Luttinger liquids"
Időpont: 2015. február 17. (kedd) 10:00 (1 óra)
Hely: MTA Wigner FK SZFI, I. épület 1. emeleti Tanácsterem

We investigate the many-body generalization of the orthogonality catastrophe by studying the Loschmidt echo of Luttinger liquids (LLs) after a global change of interaction. It decays  exponentially with system size and exhibits universal behaviour: the steady state exponent after quenching back and forth n-times between 2 LLs (bang-bang protocol) is 2n-times bigger than that of the adiabatic overlap, and depends only on the initial and final  LL parameters. These results are verified numerically by matrix-product state based methods of the XXZ Heisenberg model. An experimental setup consisting of a hybrid system containing cold atoms and a flux qubit is proposed to measure the Loschmidt echo.
További információk: http://www.szfki.hu/seminar

2015.02.17. 10:00