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Stimulated Generation of Superluminal Light Pulses via Four-wave Mixing



Ryan T. Glasser, Ulrich Vogl, Paul D. Lett


We report on the four-wave mixing of superluminal pulses, in which both the injected and generated pulses involved in the process propagate with negative group velocities. Generated pulses with negative group velocities of up to vg = −c/880 are demonstrated, corresponding to the generated pulse’s peak exiting the 1.7 cm long medium ~50 ns earlier than if it had propagated at the speed of light in vacuum, c. We also show that in some cases the seeded pulse may propagate faster than c, and that the generated conjugate pulse peak may exit the medium even earlier than the amplified seed pulse peak. We can control the group velocities of the two pulses via the seed detuning and the input seed power.
Physical Review Letters


atomic vapor, Four-wave mixing, negative group velocity, nonlinear optics, superluminal


Glasser, R. , Vogl, U. and Lett, P. (2012), Stimulated Generation of Superluminal Light Pulses via Four-wave Mixing, Physical Review Letters, [online], (Accessed April 12, 2024)
Created April 26, 2012, Updated February 19, 2017