QUANTUM ANTIFERROMAGNET AT FINITE-TEMPERATURE - A GAUGE-FIELD APPROACH | |
Note | |
关键词: SPIN DYNAMICS; GROUND-STATES; VALENCE-BOND; PEIERLS; | |
DOI : 10.1103/PhysRevB.49.4368 | |
来源: SCIE |
【 摘 要 】
Starting from the CP(N-1) model description of the thermally disordered phase of the D = 2 quantum antiferromagnet, we examine the interaction of the Schwinger-boson spin-1/2 mean-field excitations with the generated gauge (chirality) fluctuations in the framework of the 1/N expansion. This interaction dramatically suppresses the one-particle motion, but enhances the staggered static susceptibility. This means that the actual excitations in the system are represented by the collective spin-I excitations, whereas the one-particle excitations disappear from the problem. We also show that massive fluctuations of the constraint field are significant for the susceptibility calculations. A connection with the problem of a particle in random magnetic field is discussed.
【 授权许可】
Free