[Aspuru-Guzik group list] ITAMP lunch seminar: Kristin Beck (2/6)

Dear colleagues, This week we are looking forward to a talk by Kristin Beck, who is currently a graduate student in Vuletić group. Kind regards, Richard and Swati *--------------* *ITAMP Topical Lunch Discussion* Date: Friday, Feb. 6th Time: 12:00-1:30 pm Pizza will be served. Location: B-106 @ Center for Astrophysics (60 Garden Street) Directions: after entering the lobby of the CfA, turn right to enter the hallway of the B building. In the hallway, turn right again, and B-106 is there. *Speaker: *Kristin Beck- Friday, 2/4 *Title: *Cross Modulation and Nondestructive Detection of Individual Photons *Abstract: *Deterministic interactions between individual photons are a building block for optical quantum information, simulation and communication schemes. In this talk, I will present two recent experiments in which we create and study such interactions. In our system, we send photons ('EIT photons') through an ensemble of cesium atoms, where they travel as slow-light polaritons. These atoms are, in turn, coupled to a high finesse optical cavity. The atomic component of the polariton changes the transmission of light through the cavity ('cavity photons'). In the first experiment, we demonstrate the mutual cross modulation of EIT and cavity photons. Here, the polariton's presence blocks cavity light. We observe that the two initially uncorrelated beams become anticorrelated with an equal-time cross-correlation function g2(0)=0.89(1). One photon extinguishes another with a probability of 11(1)% [1]. In the second experiment, we show that the system can be used to continuously detect photons without destroying them. The polariton's presence now changes the polarization of the light transmitted through the cavity. In the correct polarization basis, the EIT and cavity photons become correlated and we measure g2(0)=6(1). [1] K. Beck, W. Chen, Q. Lin, M. Gullans, M. D. Lukin, V. Vuletic, Phys. Rev. Lett. 113, 113603 (2014) -- Dr. Swati Singh Institute for Theoretical Atomic, Molecular, and Optical Physics (ITAMP), Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-14, Cambridge, MA 02138 https://www.cfa.harvard.edu/~ssingh/