Field-induced Supersolid Phase in Spin-One Heisenberg Models

1
Field-induced Supersolid Phase in Spin-One
Heisenberg Models
The supersolid (SS) is a novel state of matter
that exhibits simultaneous diagonal (solid) and
off-diagonal (superfluid) long-range order
arising out of the interplay between competing
interactions and/or frustration. Recent
theoretical studies have shown that a spin-SS
ground state can be realized in a S1 Heisenberg
spin system with uniaxial single-ion and exchange
anisotropies in the presence of an external
magnetic field.
The ground state phases of the S1 Heisenberg
model with single-ion and exchange anisotropies
on a square lattice with varying magnetic field.
S-(Q)/N and ?s measure off-diagonal order while
Szz(Q)/N mesure diagonal order. In the SS phase
both quantities are finite.
In real quantum magnets, an effective exchange
anisotropy can be generated in S1 dimers on a
square lattice with frustrating inter-dimer
interactions. The spin-SS is induced by a field
whose Zeeman splitting is comparable to the
exchange interactions.

P. Sengupta and C. D. Batista, Field-induced
Supersolid phase in Spin-One Heisenberg models,
Phys. Rev. Lett. 98, 227201 (2007).