55th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Monday–Friday, June 3–7, 2024;
Fort Worth, Texas
Session F11: V: General Topics
8:00 AM–10:00 AM,
Wednesday, June 5, 2024
Room: Virtual Room 1
Chair: Imran Mirza, Miami University
Abstract: F11.00002 : Interference of two coherent lasers on glass surface assisted by an isotropic energy.
8:12 AM–8:24 AM
Abstract
Presenter:
Cristian Bahrim
(Lamar University)
Author:
Cristian Bahrim
(Lamar University)
The coherent superposition of cw-TEMoo laser beams on non-conductive surfaces can efficiently inhibit the interaction between a weaker beam and the surface dipoles of a dielectric material. We study the signal reflected by a soft silica glass surface due to the superposition of two 532 nm cw-TEM00 laser beams at various electronic voltages set up across the surface. A regular interference pattern with evenly distributed maxima-minima is observed. The experimental uncertainty is less than 2%, which is much less than the amplitude of the oscillations measured in the interference pattern, of 10 to 12%. We clearly observe a peak of reflectance at Brewster angle of 56.670 for silica glasses irradiated with 532nm, where the weak probe laser vanishes, because the coupling laser dominates the interaction with silica dipoles. This interaction is affected by the voltage set up across the dielectric. Thus, we observe at voltages below 0.4 volts, an interference pattern that has a perfect cos2-variation, as in any double-slit interference pattern, with a mesh of 0.760. The series of maxima-minima agree with our observation for having a minimum at 60.480 and a maximum at 61.240. At 5.3V, the optical response of silica to 532nm incident radiation changes. The non-linear Cauchy equation leads to a shift of the refractive index for silica from 1.521 to 1.724, which gives a shift in the Brewster angle from 56.670 to 60.6480. This makes the maximum reflectance due to the dominance of the coupling laser at 56.670 to shift at 60.6480. This finding indicates that the reflection of the weaker laser beam assisted by an isotropic energy can be reversed from a minimum (which shows extinction) at 60.480 for 0volts, to a maximum (which shows a strong reflection) at 60.6480 for 5.3volts. A possible application of this configuration is a new optoelectronic switch with ON (maxima) and OFF (minima) positions for the reflected light by a silica surface when an electronic voltage is set up across this surface.