Direct laser writing of relief diffraction gratings
into a bulk chalcogenide glass

Kohoutek, T; Hughes, MA; Orava, A; Mastumoto, M; Misumi, T; Kawashima, H; Suzuki, T; Ohishi, Y

Abstract

We inscribed relief diffraction gratings with periods of 6, 14, and 24 μm into the surface of Ge15Ga3Sb12S70 bulk
glass by the material’s ablation using a femtosecond λ � 800 nm Ti:sapphire pulsed laser. The laser writing was
done with sample implemented on a computer-controlled stage employing surface-to-beam alignment, laser
power, and raster pattern control. Pulse energies of 1.5, 3.0, and 4.5 μJ were focused on spot diameter of
1.5 μm, resulting in channel widths, measured on the surface, of around 4, 5, and 6 μm and depths up to
1.7 μm. The first-order diffraction efficiency of the fabricated gratings was up to 10% at λ � 650 nm. We have also
fabricated a “composite” grating combining the three relief diffraction gratings inscribed in the same position, but
with a mutual tilt. The composite grating provides complex multidirectional diffraction of the light in accordance
with geometrical arrangement and grating period of all the gratings inscribed. We propose practical applications of
femtosecond pulsed-laser surface patterning, for example, surface-relief diffraction microgratings integrated at the
ends of multimode mid-IR chalcogenide optical waveguides or on the surfaces of bare core chalcogenide glass
optical fibers used for chemical sensing.

Citation

into a bulk chalcogenide glass. Journal of the Optical Society of America B, 29(10), 2779-2786. https://doi.org/10.1364/JOSAB.29.002779

• Journal Article Type: Article
• Acceptance Date: Aug 7, 2012
• Publication Date: Sep 18, 2012
• Deposit Date: Nov 10, 2015
• Journal: Journal of the Optical Society of America B: Optical Physics (JOSA B)
• Print ISSN: 0740-3224
• Electronic ISSN: 1520-8540
• Publisher: Optical Society of America
• Volume: 29
• Issue: 10
• Pages: 2779-2786
• DOI: https://doi.org/10.1364/JOSAB.29.002779
• Publisher URL: http://dx.doi.org/ 10.1364/JOSAB.29.002779
• Related Public URLs: https://www.osapublishing.org/josab/home.cfm
• Additional Information: Funders : MEXT