Event Description
Kin Fai Mak, PhD, Cornell University
The
Hubbard model, first formulated by physicist John Hubbard in the 1960s, is a
simple theoretical model of interacting quantum particles in a lattice. The
model is thought to capture the essential physics of high-temperature
superconductors, magnetic insulators, and other complex emergent quantum
many-body ground states. Although the Hubbard model is greatly simplified as a
representation of most real materials, it has nevertheless proved difficult to
solve accurately except in the one-dimensional case. Physical realizations of
the Hubbard model in two or three dimensions, which can act as quantum
simulators, therefore have a vital role to play in solving the strong-correlation
puzzle. In this talk, I will discuss a recent experimental realization of the
two-dimensional triangular lattice Hubbard model in angle-aligned WSe2/WS2
bilayers, which form moiré superlattices because of the difference in lattice
constant between the two 2D materials. We obtain a quantum phase diagram of the
two-dimensional triangular lattice Hubbard model near the half filling by
probing both the charge and magnetic order of the system. Implications for
future studies will also be discussed. |
