Experimental method of transfer function linewidth determination for laser amplifiers using FM-to-AM conversion.

We propose an experimental method for the determination of the transfer function linewidth of a laser amplifier. This technique is based on a transfer function scan using frequency modulation to amplitude modulation (FM-to-AM) temporal modulation measurement as a function of wavelength. Using this method, we show that the output spectrum of a laser amplifier in Q-switch mode is not representative of the transfer function of the amplifier.

Second-order nonlinear optical coefficients of the monoclinic crystal BaGaSe.

We characterize the magnitude and relative signs of the second-order nonlinear optical coefficients of the biaxial crystal BaGaSe (BGSe) combining measurements of phase-matched and non-phase-matched second-harmonic generation at different wavelengths using slabs and a sphere.

Impact of the Kerr effect on FM-to-AM conversion in high-power lasers.

In order to smooth the focal spot of high-power energetic lasers, pulses are phase-modulated. However, due to propagation impairments, phase modulation is partly converted into power modulation. This is called frequency modulation to amplitude modulation (FM-to-AM conversion).

Thermal lens in diode-pumped square-section rods of Nd-doped phosphate glass and 0.5%Nd:5%Lu:CaF crystal: simulations and experiments.

We performed simulations and experiments of wavefront distortions induced by propagating through diode-pumped square-section amplifying laser rods of Nd-doped phosphate glass and 0.5:5:. We observed that depending on the material, wavefront distortions' profile can vary from a circular lens-like distortion to a complex astigmatic distortion.

Interference filters and their impact on FM-to-AM conversion: a method for investigation and characterization.

High-power nanosecond laser pulses are usually spectrally broadened via temporal phase modulations to tackle the issue of stimulated Brillouin scattering and to achieve optical smoothing of the focal spot. While propagating along the beamline, such pulses can undergo frequency modulation to amplitude modulation (FM-to-AM) conversion. This phenomenon induces modulations of the optical power that can have a strong impact on laser performance.