RQMP Research Seminar
Non-conventional orders, modulation, and
disentanglement in low-dimensional quantum systems
Gennady Chitov
Institut quantique & Département de physique Université de Sherbrooke
The research to be discussed is focused on quantum phase transitions
with non-conventional (topological) orders, such that the standard Landau
paradigm does not work in a usual way. The main goal is to advance a new
unifying theory to deal with different critical phenomena characterized by
unconventional orders. The low-dimensional systems studied are mainly chains
and ladders of quantum spins or fermions, with phases possessing distinct
hidden orders. The latter are quantitatively described by the string or brane
order parameters. The theory is advanced to calculate those quantities,
along with duality transformations mapping them onto conventional local
orders. Also, the winding numbers and zero-energy Majorana edge states, as
additional attributes of topological order, are discussed. The modulation
(i.e., appearance of oscillations in correlation functions) is related to
the analytical properties of zeros of the partition functions. The latter are
shown tocontain all information needed for analysis of phase transitions, of
modulation transitions (disorder lines), and of the ground-state factorization
(disentanglement).
Thursday, March 24th 2022, 10:30
Tele-seminar
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