Instantaneous response and suppression of SBS process in a short fiber system with binary sequence phase modulation

Area of Science:

• Nonlinear optics
• Fiber optics
• Photonics

Background:

• Stimulated Brillouin scattering (SBS) is a significant nonlinear effect in optical fibers.
• Understanding and controlling SBS is crucial for high-power fiber laser and amplifier systems.
• The kinetics of SBS buildup and suppression are complex and depend on modulation schemes.

Purpose of the Study:

• To investigate the instantaneous response of SBS in a fiber system.
• To analyze the buildup time constant of SBS kinetics.
• To examine the suppression of SBS using binary sequence phase modulation.

Main Methods:

• Analytical and experimental investigation of SBS.
• Construction of binary sequences with adjustable dwell time and period.
• Phase modulation of a 15 m short fiber system.

Main Results:

• The SBS buildup time constant was determined to be within several nanoseconds.
• Effective suppression of Stokes intensity was achieved with binary sequence modulation.
• Dwell times close to or less than the buildup time constant were most effective for suppression.
• Stokes intensity suppression showed a damped-oscillation-like trend over several sequence periods.

Conclusions:

• Binary sequence phase modulation is an effective method for controlling SBS.
• The dwell time of the modulation is a critical parameter for SBS suppression.
• This technique offers a pathway for managing nonlinear effects in fiber optic systems.