Broadband tunable optical amplification based on modulation instability characteristic of high-birefringence photonic crystal fibers

A novel high-birefringence photonic crystal fiber （HB-PCF） with two zero-dispersion wavelengths （ZDWs） is designed, and an extraordinarily high modal birefringence of 1.56×10-2 is obtained at pump wavelength λp=1850nm. With the designed HB-PCF, the effect of the pump parameters on the modulation instability （MI） in the anomalous dispersion region close to the second ZDWs of the HB-PCF is comprehensively studied in this work. A broadband and tunable optical amplification is achieved by controlling the pump power and the pump wavelength based on the combined operation of Raman effect and cross phase modulation. By optimizing the pump parameters, the amplification bandwidth along the fiber slow axis reaches 152 nm for the pump power Pp=280W and the pump wavelength λp=1675nm, while the gain bandwidth along the fiber fast axis is 165 nm for the pump power Pp=600W and the pump wavelength λp=1818nm.

High energy and long pulse generation with high-birefringence photonic crystal fibre and laser-diode pumped regenerative amplifier

We report on the generation of a high energy and long pulse for pumping optical parametric chirped-pulse amplification （OPCPA） by a high-birefringence photonic crystal fibre （HB-PCF） and a laser-diode-pumped regenerative chirped pulse amplifier. Using the femtosecond pump pulse centred at 815 nm, a 1064 nm soliton pulse is produced in the HB-PCF. After injecting it into an Nd：YAG regenerative amplifier with the glass etalons, a narrow-band amplified pulse with an energy of -4 mJ and a duration of 235 ps is achieved at a repetition rate of 10 Hz, which is suitable for being used as a pump source in the 800 nm OPCPA system.

Laser Wavelength Estimation Method Based on a High-Birefringence Fiber Loop Mirror

A simple method for the estimation of the wavelength of a fiber laser system is proposed. The method is based on the use of a high-birefringence-fiber loop mirror(HBFLM).The HBFLM exhibits a periodic transmission/reflection spectrum whose spectral characteristics are determined by the length and temperature of the high-birefringence fiber(HBF).Then,by the previous characterization of the HBFLM spectral transmission response,the central wavelength of the generated laser line can be estimated.By using a photodetector,the wav.elength of the laser line is estimated during an HBF temperature scanning by measuring the temperature at which the maximum transmitted power of the HBFLM is reached.The proposed method is demonstrated in a linear cavity tunable Er/Yb fiber laser.This method is a reliable and low-cost alternative for laser wavelength determination in short wavelength ranges without the use of specialized and expensive equipment.