Superluminal signal conversion in stimulated Brillouin scattering via an optical fiber ring resonator

TL;DR

This paper demonstrates superluminal signal propagation in stimulated Brillouin scattering within an optical fiber ring resonator, showing potential for superluminal information transfer through wavelength conversion at negative group velocities.

Contribution

First experimental evidence of superluminal signal conversion in SBS using an optical fiber ring resonator, highlighting the role of negative group velocity in optical interactions.

Findings

Superluminal Stokes and pump light observed with delays and advancements up to 93.34 ns.

Optical interaction governed by group velocity even at negative values.

Potential for superluminal information exchange via wavelength conversion.

Abstract

We report the superluminal phenomenon of both Stokes and pump light in stimulated Brillouin scattering (SBS) via an optical-fiber ring lasing resonator. In our experiment, the superluminal generation of Stokes light firstly delayed with 33.79 ns and then propagated with the advancement of 93.34 ns within an 8-m single mode fiber (SMF), when the pump power increased from the SBS threshold to a higher power. This proves the first evidence that the optical interaction is determined by the group velocity even at the negative group velocity superluminal propagation. It is important that, this implies the possibility of superluminal information interchange because the results also indicate that the signal conversion between different wavelengths can be realized at the negative group velocity propagation.