SKM 2023 – wissenschaftliches Programm
DY 43.8: Poster
Donnerstag, 30. März 2023, 13:00–16:00, P1
Many-body localization in disordered Heisenberg-type spin chain models — •Yilun Gao and Rudolf A. Römer — Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
Disordered quantum systems have become an important research topic in modern condensed matter physics ever since the discovery of Anderson localization. The investigation of many-body localization in quantum interacting systems has received much recent attention following the increase of computational power and improvement in numerical methods. One of the standard models that has been studied is the disordered spin-1/2 Heisenberg chain. It was shown that there exists a phase transition from ergodic states to many-body localized states as the disorder is increased. Here, we focus on a variant of the model where the exchange couplings between neighboring spins are taken to be disordered. We calculate the consecutive-spectral-gap ratio and its probability distribution for different system sizes and disorders. The result is compared with the case when the disorder is onsite. We average over many disorder realizations. We also plot the sample-to-sample variance against disorder and system size as a further characteristic of the phases across the MBL transition.