Conversion of cw light into a train of subnanosecond pulses using frequency modulation and the dispersion of a near-resonant atomic vapor

Abstract

Sinusoidally frequency‐modulated cw laser light is converted into a train of repetitive short pulses by passing it through a nearly resonant atomic vapor. Using a 200‐MHz modulation frequency and sodium vapor, pulses as short as 240 psec, having peak powers of 6.3 times the input power, have been obtained at 5890 Å. Calculation and experiment are in good agreement.