1211.1627 (Yasuyuki Kato)

Multi-discontinuity algorithm for world-line Monte Carlo simulations    [PDF]

Yasuyuki Kato

We introduce a novel multi-discontinuity algorithm for efficient global update of world-line configurations in Monte Carlo simulations of interacting quantum systems. This new algorithm is a generalization of the two-discontinuity algorithms introduced in Refs. [N. Prokofev, B. Svistunov, and I. Tupitsyn, Phys. Lett. A 238, 253 (1998)] and [O. Sylju{\aa}sen and A. Sandvik, Phys. Rev. E 66, 046701 (2002)] . This generalization is particularly effective for studying Bose-Einstein condensates (BEC) of composite particles. In particular, we demonstrate the utility of the generalized algorithm by simulating a Hamiltonian for an S=1 anti-ferromagnet with strong uniaxial single-ion anisotropy. The multi-discontinuity algorithm not only solves the freezing problem that arises in this limit, but also allows for computing the off-diagonal correlator that characterizes a BEC of composite particles.

View original: http://arxiv.org/abs/1211.1627