Quantum memory for photons in case of many close lying exciton resonances in solids

• Published in: The European physical journal. D, Atomic, molecular, and optical physics Vol. 53; no. 2; pp. 243 - 251
• Main Authors: Gazazyan, A. D., Gazazyan, E. A., Margaryan, A. G.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.06.2009; EDP Sciences
• Subjects: Applications of Nonlinear Dynamics and Chaos Theory; Atomic; Atomic and molecular physics; Atomic properties and interactions with photons; Classical and quantum physics: mechanics and fields; Coherent control of atomic interactions with photons; Effects of atomic coherence on propagation, absorption and amplification of light; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Molecular; Optical and Plasma Physics; Optics; Photon interactions with atoms; Physical Chemistry; Physics; Physics and Astronomy; Quantum information; Quantum Information Technology; Quantum optics; Quantum Optics and Quantum Information; Quantum Physics; Spectroscopy/Spectrometry; Spintronics; 32.80.Qk Coherent control of atomic interactions with photons; 42.50.Gy Effects of atomic coherence on propagation, absorption, and amplification of light; electromagnetically induced transparency and absorption; Continuum; Excitons; Electromagnetically induced transparency; Group velocity; Quantum optics; Autoionization; Quantum information; Configuration interaction; Quantum memory
• ISSN: 1434-6060; 1434-6079
• DOI: 10.1140/epjd/e2009-00118-5

The possibility of storage of quantum information with photons is studied in the case of resonant transitions via many close lying exciton levels in a solid with impurity -atoms. The upper levels of the impurity atom form resonant Fano states, similar to the autoionization atomic states, due to the configuration interaction with the continuum of the exciton band. In this case slowing of light pulses is shown to be realistic, in the presence of the control field, down to the group velocity much lower than that in vacuum. The possibility of storage and reconstruction of a quantum pulse is studied in the case of the instantaneous switching on/off of the control field. It is shown that the signal quantum pulse cannot be stored undistorted for differing values of Fano parameters and for non-zero two-photon detuning and decay rate between the lower levels (decoherence). However, for small difference of the Fano parameters and for small values of the two-photon detuning and the decoherence there is no distortion in the case where the length of the pulse is much longer than the linear absorption (amplification) length, so the shape and quantum state of the light pulse can be restored.