An exact investigation of a finite-size quantum spin-1/2 model of bcc3He, consisting of two interpenetrating cubes with periodic boundary conditions, is performed with an exchange Hamiltonian incorporating two-, three-, and planar four-spin exchange. Although there is qualitative agreement with the mean field phase diagram, quantum effects are much larger (up to 100% in ground state energy) than with pure Heisenberg exchange. We comment on the comparison of theory and experiment in light of the present results.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Materials Science(all)
- Condensed Matter Physics