Neodymium laser-pumped ultra-low noise tunable Brillouin fiber laser around 920†nm.

We have developed an ultra-low noise tunable Brillouin fiber laser exhibiting three orders of magnitude better frequency noise performance than the Neodymium-doped fiber laser pump and remarkable optical signal-to-noise ratio exceeding 80 dB suitable for immediate applications in coherent nonlinear conversion, quantum computing and underwater communications. In addition, we have implemented a custom optical phase-locked loop to ensure long-term stable operation and have investigated its impact on frequency noise. We demonstrate the power scalability of the single frequency (Hz-class) Brillouin laser, delivering over 500 mW with tunability across the 900 nm to 930 nm range in an all-fiber fully polarization-maintaining architecture.

High power ultralow-intensity noise continuous wave laser tunable from orange to red.

We report here on the development of a multi-Watt power tunable single frequency ultra-low noise laser system emitting around 620 nm. More than 5 W of output power is obtained between 616.5 nm and 630.8 nm using sum frequency generation of 1050 nm and 1550 nm tunable laser sources in a periodic poled lithium niobate crystal. The tunability is achieved through temperature and channel shift, and only limited by the crystal characteristics. An output power of 10.1 W and an optical-optical efficiency of 45% are reached at 624.5 nm. The relative intensity noise properties of the conversion process have been experimentally investigated in different configurations showing excellent agreement with the analytical prediction.

Ultralow-intensity noise, 10 W all-fiber single-frequency tunable laser system around 1550 nm.

We report herein on the development of a linearly polarized, single-frequency tunable laser system producing more than 10 W in the 1550 nm range, using a two-stage erbium/ytterbium co-doped fiber-based master oscillator power amplifier (MOPA) architecture. The all-fiber MOPA provides an ultralow intensity noise of -160dBc/Hz beyond 200 kHz between 1533 and 1571 nm (Δλ=38nm) at full output power and a minimum optical signal to noise ratio of 38 dB. A good stability is obtained over 4 h at maximum power for several wavelengths with peak-to-peak fluctuation less than 3% and rms below 0.5%.

Robust 17 W single-pass second-harmonic-generation at 532 nm and relative-intensity-noise investigation.

We demonstrate a 17 W single-frequency, low-intensity-noise green source at 532 nm, by single-pass second-harmonic generation of a 50 W continuous-wave fiber laser in a 30 mm MgO-doped periodically-poled stoichiometric lithium tantalate crystal. The maximum conversion efficiency is about 37%. A nearly Gaussian beam (M2<1.15 at 15 W) and low wavefront distortion are obtained. The system shows stable behavior over 100 h of uninterrupted operation. The evolution of the relative-intensity-noise transfer from the fundamental to the second harmonic is theoretically and experimentally investigated with high resolution.

Multi-GHz repetition rate, femtosecond deep ultraviolet source in burst mode derived from an electro-optic comb.

We present a femtosecond, 11.48 GHz intra-burst repetition rate deep UV source at 258 nm based on forth-harmonic generation (FHG) of an electro-optic (EO) comb operating in burst mode. Second-harmonic generation (SHG) of the burst-mode EO comb in LiB3O5 (LBO) leads to 3.7 W average power and 242 fs root-mean-square pulse duration. A second stage of SHG is further performed using two separate ß-BaB2O4 (BBO) crystals, delivering deep UV pulses at 523 mW and 294 mW, with estimated pulse durations of half-ps and sub-300 fs, respectively. At divided pulse repetition rates of 5.7 GHz and 2.9 GHz, FHG is also demonstrated, highlighting the potential of flexible repetition rate operation at the GHz level.

Ultra-low intensity noise, all fiber 365 W linearly polarized single frequency laser at 1064†nm.

We demonstrate a robust linearly polarized 365 W, very low amplitude noise, single frequency master oscillator power amplifier at 1064 nm. Power scaling was done through a custom large mode area fiber with a mode field diameter of 30 µm. No evidence of stimulated Brillouin scattering or modal instabilities are observed. The relative intensity noise is reduced down to -160 dBc/Hz between 2 kHz and 10 kHz via a wide band servo loop (1 MHz bandwidth). We achieve 350 W of isolated power, with a power stability < 0.7% RMS over 1100 hours of continuous operation and a near diffraction limited beam (M2 < 1.1).

39 W narrow spectral linewidth monolithic ytterbium-doped fiber MOPA system operating at 976 nm.

We report on a monolithic narrow spectral linewidth master oscillator power amplifier (MOPA) delivering up to 39 W around 976 nm with very high contrast. The amplifier is based on an ytterbium-doped large mode area (LMA) octagonal double clad (DC) active fiber with parameters optimized for long living three-level operation.