Phase-shifted Brillouin dynamic gratings using single pump phase-modulation: proof of concept

Area of Science:

• Photonics and Optical Engineering
• Nonlinear Optics
• Fiber Optics

Background:

• Brillouin dynamic gratings (BDGs) are crucial for optical signal processing.
• Existing methods for creating BDGs face limitations in tunability and bandwidth.
• Polarization-maintaining fiber (PMF) offers unique properties for light propagation.

Purpose of the Study:

• To propose and demonstrate novel phase-shifted Brillouin dynamic gratings (PS-BDGs).
• To utilize single pump phase-modulation (SPPM) for PS-BDG generation in PMF.
• To achieve tunable notch frequencies for advanced optical applications.

Main Methods:

• Generation of a transient PS-BDG using distinct pump pulse durations (2-ns and 100-ps) and phase modulation.
• Formation of an enhanced PS-BDG with high repetition rate (250 MHz) pump pulses.
• Experimental validation of the transient PS-BDG and demonstration of notch frequency tuning via phase shift adjustment.

Main Results:

• A transient PS-BDG with a 3-dB bandwidth of 354 MHz was successfully written.
• An enhanced PS-BDG with a deep notch depth was achieved.
• The notch frequency of the PS-BDG was shown to be tunable by altering the phase shift.

Conclusions:

• The proposed SPPM technique enables the creation of novel PS-BDGs in PMF.
• These PS-BDGs exhibit tunable notch frequencies, suitable for advanced optical systems.
• Potential applications include microwave photonics, all-optical signal processing, and radio-over-fiber networks.