Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia.
Department of Physics and Astronomy, Texas A&M University, College Station, Texas 77843, USA.
Phys Rev Lett. 2013 Feb 15;110(7):077404. doi: 10.1103/PhysRevLett.110.077404. Epub 2013 Feb 14.
Entangled photon states attract tremendous interest as the most vivid manifestation of nonlocality of quantum mechanics and also for emerging applications in quantum information. Here we propose a mechanism of generation of polarization-entangled photons, which is based on the nonlinear optical interaction (four-wave mixing) in graphene placed in a magnetic field. Unique properties of quantized electron states in a magnetized graphene and optical selection rules near the Dirac point give rise to a giant optical nonlinearity and a high rate of photon production in the mid- or far-infrared range. A similar mechanism of photon entanglement may exist in topological insulators where the surface states have a Dirac-cone dispersion and demonstrate similar properties of magneto-optical absorption.
纠缠光子态作为量子力学非局域性的最生动体现，以及在新兴的量子信息应用中引起了极大的兴趣。在这里，我们提出了一种基于磁场中石墨烯的非线性光学相互作用（四波混频）产生偏振纠缠光子的机制。在磁场中，量子化电子态的独特性质和狄拉克点附近的光学选择定则导致了中红外或远红外范围内的巨大光学非线性和高光子产生率。在拓扑绝缘体中可能存在类似的光子纠缠机制，其中表面态具有狄拉克锥色散，并表现出类似的磁光吸收特性。
