85 citations · 461 across the 27 of their papers we have counts for
8 papers · 1 filter
Exciton condensation from level repulsion: application to bilayer graphene
Harley D. Scammell, Oleg P. Sushkov
Exciton condensation in semiconductors and semimetals has long been predicted but remains elusive. In a semiconductor, condensation occurs when the exciton binding energy matches t…
Multiple universalities in order-disorder magnetic phase transitions
H. D. Scammell, O. P. Sushkov
Phase transitions in isotropic quantum antiferromagnets are associated with the condensation of bosonic triplet excitations. In three dimensional quantum antiferromagnets, such as…
Non-equilibrium quantum mechanics: A 'hot quantum soup' of paramagnons
H. D. Scammell, O. P. Sushkov
Motivated by recent measurements of the lifetime (decay width) of paramagnons in quantum antiferromagnet TlCuCl3, we investigate paramagnon decay in a heat bath and formulate an ap…
Binding of a mobile hole by an impurity potential in the t-J model: parity breaking
O. P. Sushkov, J. Oitmaa
We revisit the problem of a single hole moving in the background of the two dimensional Heisenberg antiferromagnet. The hole is loosely bound by an impurity potential. We show that…
Two-dimensional randomly-frustrated spin 1/2 Heisenberg model
J. Oitmaa, O. P. Sushkov
We investigate the properties of S=1/2 Heisenberg clusters with random frustration using exact diagonalizations. This is a model for a quantum spin glass. We show that the average…
Charge ordering and antiferromagnetic exchange in layered molecular crystals of the theta type
Ross H. McKenzie, J. Merino, J. B. Marston +1
We consider the electronic properties of layered molecular crystals of the type theta-DA, where A is an anion and D is a donor molecule such as BEDT-TTF [where BEDT-TTF is bis-…
Excitation spectrum of the S=1/2 quantum spin ladder with frustration: elementary quasiparticles and many-particle bound states
V. N. Kotov, O. P. Sushkov, R. Eder
We study the excitation spectrum of the two-chain S=1/2 Heisenberg spin ladder with additional inter-chain second-neighbor frustrating interactions. The one and two-particle excita…
Local magnetic impurities in the 2D quantum Heisenberg antiferromagnet
V. N. Kotov, J. Oitmaa, O. Sushkov
We consider the two-dimensional (2D) quantum Heisenberg antiferromagnet at zero temperature with two types of locally frustrating perturbations - an isolated ferromagnetic bond (FM…