Alberto Marino, Joint Quantum Institute, University of Maryland

Topic: "Quantum States of Light: from Generation to Applications in Quantum Information"  (Video)

Abstract: The field of quantum information holds the promise of harnessing quantum resources to provide secure communications, perform complex calculations, and enhance the sensitivity of measurements. Among those resources, one of the most important is entanglement, which is characterized by correlations stronger than allowed classically. Due to its fundamental role in quantum information science, the generation and control of entangled states of light are active research areas. In this talk I will show that non-degenerate four-wave mixing (4WM) in rubidium vapor has applications in both of these areas. In the first part of the talk I will give a general introduction into the topic of generation and characterization of entangled states of light know as twin beams. I will show how it is possible to use 4WM to generate them and will describe the advantages that are obtained with the use of this nonlinear process. In the second part of the talk I will present two applications of 4WM in quantum information: obtaining the best possible copy of a quantum state, i.e. a quantum cloner, and controlling the propagation velocity of the light carrying the entanglement, i.e. a quantum buffer. I will finish by giving a quick overview of current research projects that use twin beams for applications such as the calibration of photodiodes and the enhancement of the sensitivity of a measurement.