Jerome Porque

Single-frequency Brillouin distributed feedback fiber laser

We demonstrate a single-frequency Brillouin distributed feedback laser (DFB). The DFB laser cavity was a 12.4 cm long fiber Bragg grating with a π-phase shift offset from the grating center. It exhibited a threshold of 30 mW and conversion efficiency from pump to Stokes wave as high as 27%. Higher-order Stokes waves were suppressed by more than 20 dB. The Stokes output of the laser could be obtained in either the forward or backward direction, simply by changing the orientation of the offset of the discrete phase shift with respect to the pump propagation direction. The DFB laser operated over a pump frequency range of 1.2 GHz, more than 60 times larger than the SBS gain bandwidth.

Raman fiber distributed feedback lasers.

We demonstrate fiber distributed feedback (DFB) lasers using Raman gain in two germanosilicate fibers. Our DFB cavities were 124 mm uniform fiber Bragg gratings with a π phase shift offset from the grating center. Our pump was at 1480 nm and the DFB lasers operated on a single longitudinal mode near 1584 nm. In a commercial Raman gain fiber, the maximum output power, linewidth, and threshold were 150 mW, 7.5 MHz, and 39 W, respectively. In a commercial highly nonlinear fiber, these figures improved to 350 mW, 4 MHz, and 4.3 W, respectively. In both lasers, more than 75% of pump power was transmitted, allowing for the possibility of substantial amplification in subsequent Raman gain fiber.

Demonstration of a Raman fiber distributed feedback laser

We demonstrate a fiber distributed feedback laser oscillator using Raman gain in a 124mm germanosilicate fiber grating at 1584nm. We measure a 6MHz signal linewidth, more than 1000× smaller than previous Raman fiber laser oscillators.

Multicore fiber distributed feedback lasers.

We demonstrate parallel fabrication of seven fiber distributed feedback (DFB) lasers in a hexagonally arrayed multicore core Er doped fiber with 40 μm core spacing. DFB grating cavities 8 cm long and operating near 1545 nm were fabricated with a single UV inscription exposure. We observed dual polarization, single longitudinal mode operation with a linewidth below 300 kHz for each laser.

A seven core fiber DFB

We demonstrate fiber DFB lasers in a seven core Er doped fiber. DFB grating cavities were fabricated in all cores at once via a single UV exposure. Lasing was observed in all seven cores.

Highly Efficient Distributed Feedback Brillouin Fiber Laser

An efficient single frequency distributed feedback (DFB) Brillouin fiber laser producing 22mW of Stokes output, using 81mW of pump from a semiconductor DFB laser, is shown. The laser operated for a pump frequency detuning >1GHz.

Fiber DFB laser bend sensor with RF signal interrogation

We report on the properties of a dual-polarization distributed feedback fiber laser as the fiber cavity is bent. We show that the RF polarization beat note can sense fiber bend and temperature.

Distributed feedback fiber laser employing Brillouin gain

A single frequency distributed feedback Brillouin fiber laser exhibiting a threshold of 30 mW, and pump-to-Stokes conversion efficiency of 27% is shown. The Brillouin laser operates over a pump frequency detuning range exceeding 1 GHz.

Raman fiber DFBs in highly nonlinear germanoscilate fibers

We report detailed comparisons of Raman fiber DFB lasers using small effective area highly nonlinear fiber and conventional Raman gain fiber. Improvements in threshold, linewidth and output power are observed.