Continuous-wave self-deflection effect in sodium vapor
نویسنده
چکیده
Observations of the self-deflection effect for an asymmetrical continuous-wave laser beam in sodium vapor are described, and comparisons based on theoretical calculations are made. A self-bending angle as large as eight diffraction widths was recorded, and strong attenuation of the on-axis radiation due to self-bending was measured. At -200'C the self-deflection angle increased linearly with beam power, and we determined that (n2)max -10-7 cm /W for intensities below 220 W/cm 2 . While numerical calculations, based on an inhomogeneously broadened two-level system, predict strong saturation of the self-bending effect, we observed only moderate saturation.
منابع مشابه
Self-bending of a cw laser beam in sodium vapor.
Continuous-wave self-deflection of an asymmetrical laser beam, with a deflection angle up to eight diffraction widths, and strong attenuation of the on-axis radiation were achieved in a short sodium-vapor cell. We determined that the nonlinear refractive index Deltan varied almost linearly with intensity I, Deltan approximately n(2)I, with n(2) ~ -10(-7) cm(2)/W at ~200 degrees C and intensitie...
متن کاملConical emission due to four-wave mixing enhanced by the ac Stark effect in self-trapped filaments of light.
Experimental evidence is presented that shows that the conical emission often found surrounding a near-resonant laser beam after it passes through an atomic vapor is due to nondegenerate four-wave mixing enhanced by the ac Stark effect. We demonstrate self-trapping of a pulsed dye-laser beam in sodium vapor for wavelengths 0.04 to 10 A shorter than that of the D(2) resonance and show that the f...
متن کاملSingle-beam squeezed-state generation in sodium vapor and its self-focusing limitations.
We describe an experiment that generates squeezed states by means of forward four-wave mixing in sodium vapor with a single optical beam. The single-beam arrangement maximizes the pump-probe spatial overlap in the nonlinear medium. Self-focusing (or self-defocusing) is found to be the major limiting factor in achieving optimal squeezing.
متن کاملDistortion-free gain and noise correlation in sodium vapor with four-wave mixing and coherent population trapping.
We observed optical gain as great as 30 with nearly distortion-free beam propagation in optically dense sodium vapor, using four-wave mixing. Moreover, 15-dB classical noise correlations were seen in the amplified probe and conjugate beams. To achieve this performance in such a strongly absorbing medium, one must suppress unwanted absorption and self-focusing effects. This is accomplished with ...
متن کاملContinuous-wave photothermal deflection spectroscopy with fundamental and harmonic responses.
A diffraction theory of continuous-wave photothermal deflection (PD) spectroscopy with fundamental and harmonic responses is presented. The displacement of the probe beam centroid is found to be a rigorous measurement of PD effect, which leads to a set of analytical solutions to the fundamental and the second-order harmonics. Harmonics are caused by the diffraction of the probe beam in the mira...
متن کامل