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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Data transfer rates and parallelism of two-photon memories

James H. Strickler

Published Nov 9, 1993• 1 citation

Abstract

Data transfer rates of recently proposed 3D two-photon memories are potentially limited by repetition rates of pulsed lasers. Herein we propose a method of spatially and temporally multiplexing pulse from a multi-Watt, 100 MHz repetition rate, sub-picosecond pulse width mode-locked laser to a linear array of parallel data channels in order to increase the two- photon writing rate. Nearby channels are desynchronized so that pulses incident on adjacent regions of the storage medium do not overlap far from the focal plane. This prevents pairs of photons directed to proximate bits from being simultaneously absorbed in regions of beam overlap which would otherwise degrade the optical sectioning property of the two-photon absorption method. This method may be applied to an earlier proposed architecture that uses 2D arrays of channels for massively parallel memories. Our modified writing method obviates the necessity for intersecting beams and thus reduces the diffraction limit to the storage density of this alternative approach.

DOI: 10.1117/12.163607

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