Accession Number : ADP007876

Title :   Investigation of Carrier Transport in Photorefractive Superlattices by Time-Correlated Photon Counting,

Corporate Author : AT AND T BELL LABS MURRAY HILL NJ

Personal Author(s) : Lacaita, Andrea ; Ralph, Stephen E. ; Capasso, Federico ; Malik, Roger J.

Report Date : 22 MAY 1992

Pagination or Media Count : 4

Abstract : Recently a new class of photorefractive structures has been demonstrated. These devices rely on the spatial separation of photogenerated electrons and holes to produce a large refractive index modulation via the electro-optic effect and might have potential for all optical switching applications. One of these devices consists of an asymmetric 6-doped superlattice which is optically excited by a picosecond laser source. The resulting space charge field produced by charge separation creates a refractive index change of 3.8xl0-4 at a pump energy density of 40 fJ/um2. In this paper we report the first time-resolved studies of the carrier relaxation in these structures. The measurements were performed by a Time Correlated Photon Counting (TCPC) technique.

Descriptors :   *OPTICAL SWITCHING, *REFRACTION, DENSITY, ELECTRONS, ENERGY, INDEXES, LASERS, MEASUREMENT, MODULATION, OPTICS, PHOTONS, PUMPS, REFRACTIVE INDEX, RELAXATION, SEPARATION, SPACE CHARGE, STRUCTURES, SUPERLATTICES, SWITCHING, CHARGE CARRIERS, TRANSPORT PROPERTIES, ELECTROOPTICS.

Subject Categories : Electrooptical and Optoelectronic Devices

Distribution Statement : APPROVED FOR PUBLIC RELEASE