Double-layer Heisenberg antiferromagnet at finite temperature: Brueckner theory and quantum Monte Carlo simulations
Double-layer Heisenberg antiferromagnet at finite temperature: Brueckner theory and quantum Monte Carlo simulations
The double-layer Heisenberg antiferromagnet with intra- and inter-layer couplings $J$ and $J_\perp$ exhibits a zero temperature quantum phase transition between a quantum disordered dimer phase for $g>g_c$ and a Neel phase with long range antiferromagnetic order for $g<g_c$, where $g=J_\perp/J$ and $g_c \approx 2.5$. We consider the behavior of the …