Matthias Punk, Subir Sachdev
We calculate the Fermi surface of electrons in hole-doped, extended t-J
models on a square lattice in a regime where no long-range antiferromagnetic
order is present, and no symmetries are broken. Using the "spinon-dopon"
formalism of Ribeiro and Wen, we show that short-range antiferromagnetic
correlations lead to a reconstruction of the Fermi surface into hole pockets
which are not necessarily centered at the antiferromagnetic Brillouin zone
boundary. The Brillouin zone area enclosed by the Fermi surface is proportional
to the density of dopants away from half-filling, in contrast to the
conventional Luttinger theorem which counts the total electron density. This
state realizes a "fractionalized Fermi liquid" (FL*), which has been proposed
as a possible ground-state of the underdoped cuprates; we note connections to
recent experiments. We also discuss the quantum phase transition from the FL*
state to the Fermi liquid state with long-range antiferromagnetic order.
View original:
http://arxiv.org/abs/1202.4023
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