Scaling of Berry's phase close to the Dicke quantum phase transition
Scaling of Berry's phase close to the Dicke quantum phase transition
复制标题
DOI：
10.1209/epl/i2006-10270-x
复制
发表时间：
2006-04
期刊：
影响因子：
1.8
通讯作者：
F. Plastina;G. Liberti;A. Carollo
中科院分区：
文献类型：
--
作者：
F. Plastina;G. Liberti;A. Carollo
我们讨论了绝热迪凯模型中几何相位的热力学和有限尺度标度性质，描述了N量子比特寄存器耦合到慢振子模式的量子相变.我们表明，在热力学极限，一个非零的Berry相位获得，只有当参数空间中的路径是围绕临界点。此外，我们研究了有限尺寸系统的临界行为的前兆，并得到了Berry相的1/N展开的首阶和临界指数。
We discuss the thermodynamic and finite-size scaling properties of the geometric phase in the adiabatic Dicke model, describing a quantum phase transition for an N qubit register coupled to a slow oscillator mode. We show that, in the thermodynamic limit, a non-zero Berry phase is obtained only if a path in parameter space is followed that encircles the critical point. Furthermore, we investigate the precursors of this critical behavior for a system with finite size and obtain the leading orders in the 1/N expansion of the Berry phase and its critical exponent.