P. Soan | Imperial College London (original) (raw)
Uploads
Papers by P. Soan
Journal of the Optical Society of America B, 1992
Instrumentation & development, 1994
Abstract Pump transmission and signal gain in a laser pumped dye amplifier have been modelled at ... more Abstract Pump transmission and signal gain in a laser pumped dye amplifier have been modelled at saturating pump and signal intensities and a comparison has been made to experimental measurements. It is shown that the transmission of the pump beam can be strongly controlled by the intensity of the signal beam. It is demonstrated that this process can be used as the basis for a device for high power optical switching, spatial beam control and image transfer in dye media.
Optics Letters, 1992
Four-wave mixing in a saturated gain medium has been modeled numerically, and the predictions for... more Four-wave mixing in a saturated gain medium has been modeled numerically, and the predictions for the reflectivity have been compared with experiments carried out in the laser-pumped dye Rhodamine 6G. It is demonstrated that the saturable absorption of the inversion laser pump has a dramatic influence on the intensity dependence of the four-wave-mixing reflectivity.
Optics Letters, 1994
We demonstrate, for the first time to our knowledge, a self-starting stimulated-Brillouin-scatter... more We demonstrate, for the first time to our knowledge, a self-starting stimulated-Brillouin-scattering phaseconjugate resonator in a flash-lamp-pumped dye-laser system. The brightness of the laser is increased by a factor of 40 compared with that of an equivalent plane-]plane conventional resonator.
Journal of the Optical Society of America B, 1994
We experimentally demonstrate and theoretically analyze practical aspects of using a laser-pumped... more We experimentally demonstrate and theoretically analyze practical aspects of using a laser-pumped dye medium as an ultrafast (10-ps) optically addressed spatial light modulator for application with high-power radiation. Optical modulation of the absorption of a high-power pump beam is produced by a relatively weak (control) beam that is experiencing stimulated emission. The intensity of the control beam required for strong switching of the pump-beam transmission is determined by the gain that is due to stimulated emission at the control-beam frequency. A practical limitation on the gain that is due to excited-state absorption of the pump frequency is described. We demonstrate the application of the dye medium spatial light modulator for high-resolution image transfer and determine the resolution limit of the transfer process. Experimental demonstration is made of optical image processing (edge enhancement). The control beam can also be generated by self-lasing in feedback geometries, and pump transmission can be controlled by the strength of the feedback.
IEEE Journal of Quantum Electronics, 1999
A two-channel, repetitively pulsed laser was studied. The main features of this laser were the co... more A two-channel, repetitively pulsed laser was studied. The main features of this laser were the compensation of aberration and polarization distortions in Nd : YAG crystals and the summation of two channels of radiation into a single diffractionlimited beam with a pulse energy up to 5 J.
Journal of the Optical Society of America B, 1992
The performance of a phase-conjugate cavity using a stimulated Brillouin scattering (SBS) reflect... more The performance of a phase-conjugate cavity using a stimulated Brillouin scattering (SBS) reflector to control the spatial and spectral output of a coaxial flash-lamp-pumped dye laser is reported. The divergence of the output from the phase-conjugate laser cavity was measured and shown to be a significant improvement over that of the conventional resonator. Both gaseous and liquid nonlinear materials were used as the SBS media. With the gaseous medium periods of oscillation exceeding 1 us were observed, which is longer than the FWHM duration of the output from the comparable conventional resonator.
Journal of the Optical Society of America B, 1992
Instrumentation & development, 1994
Abstract Pump transmission and signal gain in a laser pumped dye amplifier have been modelled at ... more Abstract Pump transmission and signal gain in a laser pumped dye amplifier have been modelled at saturating pump and signal intensities and a comparison has been made to experimental measurements. It is shown that the transmission of the pump beam can be strongly controlled by the intensity of the signal beam. It is demonstrated that this process can be used as the basis for a device for high power optical switching, spatial beam control and image transfer in dye media.
Optics Letters, 1992
Four-wave mixing in a saturated gain medium has been modeled numerically, and the predictions for... more Four-wave mixing in a saturated gain medium has been modeled numerically, and the predictions for the reflectivity have been compared with experiments carried out in the laser-pumped dye Rhodamine 6G. It is demonstrated that the saturable absorption of the inversion laser pump has a dramatic influence on the intensity dependence of the four-wave-mixing reflectivity.
Optics Letters, 1994
We demonstrate, for the first time to our knowledge, a self-starting stimulated-Brillouin-scatter... more We demonstrate, for the first time to our knowledge, a self-starting stimulated-Brillouin-scattering phaseconjugate resonator in a flash-lamp-pumped dye-laser system. The brightness of the laser is increased by a factor of 40 compared with that of an equivalent plane-]plane conventional resonator.
Journal of the Optical Society of America B, 1994
We experimentally demonstrate and theoretically analyze practical aspects of using a laser-pumped... more We experimentally demonstrate and theoretically analyze practical aspects of using a laser-pumped dye medium as an ultrafast (10-ps) optically addressed spatial light modulator for application with high-power radiation. Optical modulation of the absorption of a high-power pump beam is produced by a relatively weak (control) beam that is experiencing stimulated emission. The intensity of the control beam required for strong switching of the pump-beam transmission is determined by the gain that is due to stimulated emission at the control-beam frequency. A practical limitation on the gain that is due to excited-state absorption of the pump frequency is described. We demonstrate the application of the dye medium spatial light modulator for high-resolution image transfer and determine the resolution limit of the transfer process. Experimental demonstration is made of optical image processing (edge enhancement). The control beam can also be generated by self-lasing in feedback geometries, and pump transmission can be controlled by the strength of the feedback.
IEEE Journal of Quantum Electronics, 1999
A two-channel, repetitively pulsed laser was studied. The main features of this laser were the co... more A two-channel, repetitively pulsed laser was studied. The main features of this laser were the compensation of aberration and polarization distortions in Nd : YAG crystals and the summation of two channels of radiation into a single diffractionlimited beam with a pulse energy up to 5 J.
Journal of the Optical Society of America B, 1992
The performance of a phase-conjugate cavity using a stimulated Brillouin scattering (SBS) reflect... more The performance of a phase-conjugate cavity using a stimulated Brillouin scattering (SBS) reflector to control the spatial and spectral output of a coaxial flash-lamp-pumped dye laser is reported. The divergence of the output from the phase-conjugate laser cavity was measured and shown to be a significant improvement over that of the conventional resonator. Both gaseous and liquid nonlinear materials were used as the SBS media. With the gaseous medium periods of oscillation exceeding 1 us were observed, which is longer than the FWHM duration of the output from the comparable conventional resonator.