Superluminal and slow light in {lambda}-type three-level atoms via squeezed vacuum and spontaneously generated coherence

Journal Article · Wed Jun 15 04:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.71.063805· OSTI ID:20717966

Carreno, F; Calderon, Oscar G; Anton, M A ^[1]; Gonzalo, Isabel ^[2]

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1. Escuela Universitaria de Optica, Universidad Complutense de Madrid, C/ Arcos de Jalon s/n, 28037 Madrid (Spain)
2. Facultad de Ciencias Fisicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 (Spain)

We study the dispersion and absorption spectra of a weak probe in a {lambda}-type three-level atomic system with closely ground sublevels driven by a strong field and damped by a broadband squeezed vacuum. We analyze the interplay between the spontaneous generated coherence and the squeezed field on the susceptibility of the atomic system. We find that by varying the intensity of the squeezed field the group velocity of a weak pulse can change from subluminal to superluminal. In addition we exploit the fact that the properties of the atomic medium can be dramatically modified by controlling the relative phase between the driving field and the squeezed field, allowing us to manipulate the group velocity at which light propagates. The physical origin of this phenomenon corresponds to a transfer of the atomic coherence from electromagnetically induced transparency to electromagnetically induced absorption. Besides, this phenomenon is achieved under nearly transparency conditions and with negligible distortion of the propagation pulse.

• OSTI ID: 20717966
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 6 Vol. 71; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ABSORPTION
ABSORPTION SPECTRA
ATOMS
ENERGY LEVELS
LIGHT TRANSMISSION
OPACITY
OPTICAL DISPERSION
OPTICS
PULSES
VELOCITY