Memory for Light as a Quantum Process

Abstract

We report complete characterization of an optical memory based on electromagnetically induced transparency. We recover the superoperator associated with the memory, under two different working conditions, by means of a quantum process tomography technique that involves storage of coherent states and their characterization upon retrieval. In this way, we can predict the quantum state retrieved from the memory for any input, for example, the squeezed vacuum or the Fock state. We employ the acquired superoperator to verify the nonclassicality benchmark for the storage of a Gaussian distributed set of coherent states.

Fisher information and asymptotic normality in system identification for quantum Markov chains

“…With a more careful analysis of the speed of convergence in (9), it can be shown that the weak LAN can be upgraded to the strong version described by (5) and (6) [20].…”

“…Recently, statistical inference has become an indispensable tool in quantum engineering tasks such as state preparation [5,6] , precision metrology [7,8], quantum process tomography [9,10], state transfer and teleportation [11,12], continuous variables tomography [13,14].…”

Quantum state tomography of slow and stored light

“…This type of "quantum process tomography" was performed by Lobino et al using single mode coherent states. 20 A generic measurement system would be able to extend these results to multimode states.…”

All-Optically Controlled Quantum Memory for Light with a Cavity-Optomechanical System

“…So far, successful demonstrations of quantum light storage have been used in atomic vapor [4], doped solid [5], and quantum cavity system [6,7]. Equally exciting is the possibility that these results will lead to useful applications in the fields of telecommunications and optical buffer [8]. There are several possible techniques of implementing quantum light memory such as electromagnetically induced transparency (EIT) [9], coherent population oscillation (CPO) [10], Raman and Brillouin amplification [11], among others [12].…”