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Physical Review A

Optical control of superluminal propagation of nanosecond laser pulses

Emilio Ignesti, Federico Tommasi, Roberto Buffa, Lorenzo Fini, Emiliano Sali, Stefano Cavalieri

Published Mar 25, 2013• 4 citations
Publisher

Abstract

We present an all-optical incoherent control of superluminal propagation of a 3 ns laser pulse. The experimental results show an induced advance up to 400 ps, without significant distortion, continuously controlled by the characteristics of a control pulse. The measurements agree with numerical simulation.
DOI
10.1103/physreva.87.033828

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I derive a simple model for the propagation of a smooth pulse detuned outside a gain line. The pulse moves superluminally and with little distortion provided the medium is not longer than the saturation length. If the medium is longer than this, two effects occur: amplified spontaneous emission interferes with the pulse (although this interference averages to zero over many experiments) and the magnitude of the group delay increases only logarithmically with the length. I argue that both of these effects are inherent to any optical system with gain. Numerical simulations of the superluminal pulse agree with the model presented. \textcopyright{} 1996 The American Physical Society.
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