Département de Physique, Université de Sherbrooke, Québec, Canada.
Phys Rev Lett. 2010 Feb 5;104(5):050504. doi: 10.1103/PhysRevLett.104.050504.
We present a family of algorithms, combining real-space renormalization methods and belief propagation, to estimate the free energy of a topologically ordered system in the presence of defects. Such an algorithm is needed to preserve the quantum information stored in the ground space of a topologically ordered system and to decode topological error-correcting codes. For a system of linear size l, our algorithm runs in time logl compared to l{6} needed for the minimum-weight perfect matching algorithm previously used in this context and achieves a higher depolarizing error threshold.
我们提出了一组算法，结合实空间重整化方法和置信传播，来估计存在缺陷的拓扑有序系统的自由能。这种算法是为了保护拓扑有序系统的基态空间中存储的量子信息和对拓扑纠错码进行解码而需要的。对于线性大小为 l 的系统，我们的算法的运行时间为 logl，而之前在这个上下文中使用的最小权完美匹配算法则需要 l{6}，并且我们的算法实现了更高的去极化错误阈值。
