ELFT HÍRADÓ

[tcsaba <tcsaba AT eik.bme.hu>]

                 M E G H Í V Ó - I N V I T A T I O N

    Seminar Series of the Department of Theoretical Physics at the
           Budapest University of Technology and Economics


                           Balázs Dóra
              (Department of Theoretical Physics,
        Budapest University of Technology and Economics)


         Out-of-time-ordered correlators in Luttinger liquids


Information scrambling and the butterfly effect in chaotic quantum 
systems can be diagnosed by out-of-time-ordered commutators through an 
exponential growth and large late time value. We show that the latter 
feature shows up in a strongly correlated many-body system, a Luttinger 
liquid, whose density fluctuations we study at long and short 
wavelengths, both in equilibrium and after a quantum quench. We find 
rich behaviour combining robustly universal and non-universal features. 
For the short
wavelength density operator, out-of-time-ordered commutators reach a 
sizeable value after the light cone only in an interacting Luttinger 
liquid, where the bare excitations break up into collective modes. We 
benchmark our findings numerically on an interacting spinless fermion 
model in 1D, and find persistence of central features even in the 
non-integrable case. As a non-universal feature, the short time growth 
exhibits a distance dependent power.


Időpont: 2018. szeptember 14. péntek, 10:15
Helyszín: BME Fizikai Intézet, Elméleti Fizika Tanszék,
Budafoki út 8. F-épület, III lépcsőház, szemináriumi szoba