Intermodal stimulated Brillouin scattering in two-mode fibers

Optics Letters, Vol. 38, Issue 11, pp. 1805-1807 (2013).

Kwang Yong Song, Yong Hyun Kim, Byoung Yoon Kim.

 

Department of Physics, Chung-Ang University, Seoul 156-756, South Korea and

Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea.

 

Abstract

 

Characterization of stimulated Brillouin scattering (SBS) in an elliptic-core two-mode fiber is experimentally demonstrated. The LP01 or LP11 mode is selectively launched to a fiber under test by a mode-selective coupler as a Brillouin pump, and the Brillouin gain spectra are analyzed for different mode pairs of the pump and probe waves. Intermodal SBS between counterpropagating LP01 and LP11 modes is observed, and the efficiency is measured to be about 58% of that of the SBS between the LP01 modes.

© 2013 Optical Society of America

Go To Journal

 

Additional Information: 

Recently, mode division multiplexing (MDM) with two- or few-mode fibers has attracted considerable attention in the society of optical communications as a new dimension for increasing the capacity of transmission systems. An elliptic-core (e-core) two-mode fiber (TMF) is the simplest platform of MDM by supporting only two optical modes (LP01 and LP11) with stable orientation of the lobes in the LP11 mode. Stimulated Brillouin scattering (SBS) is one of dominant nonlinear phenomena observed in optical fibers with the lowest threshold power of about mW level. In SBS, counter-propagating optical waves with different frequencies interact through an acoustic wave guided in the core of the fiber, resulting in energy transfer from the higher-frequency optical wave (or pump wave) to the lower frequency one (or probe wave). So far, most of the studies on SBS in optical fibers have been performed based on single-mode fibers (SMF’s) In this work, we present the first experimental demonstration of the SBS in a TMF, where the characterization of the SBS between the same and different optical modes is conducted. A mode selective coupler (MSC) is used to selectively launch the LP01 or LP11 mode to the TMF as a Brillouin pump, and the Brillouin gain spectra (BGS) of counter-propagating probe waves are analyzed for different pairs of the pump-probe modes (LP01-LP01, LP11-LP01, LP01-LP11, LP11-LP11). Intermodal SBS is observed between the LP01 and LP11 modes, and the efficiency is measured to be about 58% of that of the SBS between the LP01 modes. The efficiency of the SBS between the LP11 modesis measured to be 47% of that between the LP01 modes. The intermodal SBS can be observed in circular-core two- or few-mode fibers as well, and we expect this phenomenon to become a new platform providing unique functions for the applications of two- or few-mode fibers.

 

Intermodal stimulated Brillouin scattering in two-mode fibers

Check Also

Enhancing Mid-Infrared Er,Cr:YSGG Laser Pulse Performance via LiNbO₃ Acousto-Optic Q-Switching and Thermal Lensing Compensation - Advances in Engineering

Enhancing Mid-Infrared Er,Cr:YSGG Laser Pulse Performance via LiNbO₃ Acousto-Optic Q-Switching and Thermal Lensing Compensation