title: Lateral shearing interferometer for measuring photoinduced refractive index change in As(2)S(3).
abstract: We have built and demonstrated a lateral shearing interferometer as a process engineering and control tool for the fabrication and characterization of direct-laser-written waveguide structures in chalcogenide glasses. Photoinduced change in refractive index of 0.154+/-0.002 was measured for as-deposited amorphous As(2)S(3) thin films at 633 nm with an estimated measurement uncertainty of 1.3% for this air-gap interferometer configuration. The simple design of this interferometer can easily be adapted to other wavelengths including mid- and long-wave infrared regions to measure changes in refractive index or material inhomogeneities in transmissive materials.
authors.affiliation: Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, USA.
authors.forename: Kannan
authors.initials: K
authors.lastname: Krishnaswami
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Bernacki
authors.forename: Nicolas
authors.initials: N
authors.lastname: Hô
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Allen
authors.forename: Norman C
authors.initials: NC
authors.lastname: Anheier