Mott glass phase in a diluted bilayer Heisenberg quantum antiferromagnet

[摘要] We use quantum Monte Carlo simulations to study a dimer-diluted S = 1/2 Heisenberg model on a bilayer square lattice with intralayer interaction J1and interlayer interaction J2. Below the classical percolation threshold pc, the system has three phases reachable by tuning the interaction ratio g = J2/J1: a Néel ordered phase, a gapless quantum glass phase, and a gapped quantum paramagnetic phase. We present the ground-state phase diagram in the plane of dilution p and interaction ratio g. The quantum glass phase is certified to be of the gapless Mott glass type, having a uniform susceptibility vanishing at zero temperature T and following a stretched exponential form at T > 0; χuexp(-b/Tα) with α

[发布机构] State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou; 510275, China^1;Department of Physics, Boston University, 590 Commonwealth Avenue, Boston; MA; 02215, United States^2

[效力级别] 计算机科学 [学科分类] 计算机科学（综合）

[关键词] Ground state phase diagram;Interlayer interactions;Percolation thresholds;Phase transition point;Quantum antiferromagnets;Quantum Monte Carlo simulations;Stretched exponential;Uniform susceptibility