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
       Open Group Seminar of the "Exotic Quantum Phases" Group


                          Karlo Penc
               (Wigner Research Centre for Physics)


       Berry phase induced dimerization in one-dimensional
                     quadrupolar systems


We investigate the effect of the Berry phase on quadrupoles that occur, 
for example, in the low-energy description of spin models. Specifically, 
we study here the one-dimensional bilinear-biquadratic spin-one model. 
An open question for many years about this model is whether it has a 
nondimerized fluctuating nematic phase. The dimerization has recently 
been proposed to be related to Berry phases of the quantum fluctuations. 
We use an effective low-energy description to calculate the scaling of 
the dimerization according to this theory and then verify the 
predictions using large scale density-matrix renormalization group 
simulations, giving good evidence that the state is dimerized all the 
way up to its transition into the ferromagnetic phase. We furthermore 
discuss the multiplet structure found in the entanglement spectrum of 
the ground state wave functions.


Időpont: 2017. március 17. péntek, 10:15
Helyszín: BME Fizikai Intézet, Elméleti Fizika Tanszék,
Budafoki út 8. F-épület, III lépcsőház, szemináriumi szoba