Random antireflective nanostructuring on binary near-wavelength period gratings

Karteek Kunala; Menelaos K. Poutous

doi:10.1117/1.OE.57.8.087106

29 August 2018 Random antireflective nanostructuring on binary near-wavelength period gratings

Karteek Kunala, Menelaos K. Poutous

Author Affiliations +

Optical Engineering, Vol. 57, Issue 8, 087106 (August 2018). https://doi.org/10.1117/1.OE.57.8.087106

Abstract

Fresnel reflection losses have been reduced by the fabrication of random nanostructures on optical component surfaces, acting as an antireflective treatment. These structures have shown a broadband enhancement over a wide range of angle-of-incidence and polarization insensitivity. The random nanostructures were fabricated on pre-existing, near-wavelength period, fused silica binary gratings, with periods of 1.595 and 1.166 μm, respectively. The diffractive properties and the efficiency were measured and compared prior and postimplementation of the random nanostructures. The postprocessed gratings retained the diffractive properties of the original gratings, such as the propagating diffraction order angles, period, and the fill factor. A selectable multiwavelength He–Ne laser working at 594, 612, and 633 nm was used to test the gratings for both incident polarizations, S (TE) and P (TM). The data were collected at normal and Bragg incidence. The Fresnel reflection was suppressed by a factor of 10 postprocessing, resulting in a reflected intensity of 0.5% to 1.0% for 1.595-μm period grating and around 0.5% to 4% for 1.166-μm period grating. A 10% enhancement was observed for the combined transmission diffraction efficiency at S polarization for the 1.166-μm grating. Beam profiles of the diffracted light show no adverse changes due to the random nanostructuring on both the gratings. The results indicate that random nanostructures can be an antireflective treatment for pre-existing binary gratings, without adverse effects on the grating diffractive properties and beam profiles.

Citation Download Citation

Karteek Kunala and Menelaos K. Poutous "Random antireflective nanostructuring on binary near-wavelength period gratings," Optical Engineering 57(8), 087106 (29 August 2018). https://doi.org/10.1117/1.OE.57.8.087106

Received: 25 April 2018; Accepted: 8 August 2018; Published: 29 August 2018

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available