Vidal G, Latorre J I, Rico E, Kitaev A
Institute for Quantum Information, California Institute of Technology, Pasadena, California 91125, USA.
Phys Rev Lett. 2003 Jun 6;90(22):227902. doi: 10.1103/PhysRevLett.90.227902. Epub 2003 Jun 2.
Entanglement, one of the most intriguing features of quantum theory and a main resource in quantum information science, is expected to play a crucial role also in the study of quantum phase transitions, where it is responsible for the appearance of long-range correlations. We investigate, through a microscopic calculation, the scaling properties of entanglement in spin chain systems, both near and at a quantum critical point. Our results establish a precise connection between concepts of quantum information, condensed matter physics, and quantum field theory, by showing that the behavior of critical entanglement in spin systems is analogous to that of entropy in conformal field theories. We explore some of the implications of this connection.
量子纠缠是量子理论中最引人入胜的特征之一，也是量子信息科学中的一种主要资源，预计它在量子相变的研究中也将发挥关键作用，在量子相变中它导致了长程关联的出现。我们通过微观计算研究了自旋链系统中量子纠缠在量子临界点附近以及处于量子临界点时的标度性质。我们的结果通过表明自旋系统中临界纠缠的行为类似于共形场论中熵的行为，在量子信息、凝聚态物理和量子场论的概念之间建立了精确的联系。我们探讨了这种联系的一些含义。
