Current carriers in a Hubbard antiferromagnet
Abstract
The possible types of singleparticle excitations of a Hubbard antiferromagnetic semiconductor are investigated, starting from the selfconsistentfield approximation. Unlike the preceding studies, the excitation is described in the general case by a superposition of states of a freely propagating electron, an uncoupled electronspin wave pair, and a coupled electronspin wave pair. It is shown in this case that in a finite interval of problem parameter values there exists an isolated lowlying band, corresponding to lowmobility excitations with substantial largeradius impurity quasioscillators. It is also shown that in the strong interaction limit the excitation bandwidth remains finite due to the contribution of bound states.
 Publication:

Soviet Physics Journal
 Pub Date:
 September 1988
 DOI:
 10.1007/BF00895982
 Bibcode:
 1988SvPhJ..31..732S