Browse Prior Art Database

ACHIEVING EFFICIENT SHG IN THIN FILM WAVEGUIDES BY ADJUSTING WAVEGUIDE THICKNESS

IP.com Disclosure Number: IPCOM000023981D
Original Publication Date: 1979-Jun-30
Included in the Prior Art Database: 2004-Apr-01
Document File: 2 page(s) / 345K

Publishing Venue

Xerox Disclosure Journal

Abstract

By second harmonic generation (SHG), frequency doubling can be obtained from infrared diode laser sources to create visible photons, such as 4500A (blue) photons. In such devices, the laser, such as DFB laser, is optically coupled to a thin film waveguide in which the frequency doubling takes place. By accurately controlling the thickness of the waveguide to a predetermined value so that the propagation constants of the generated second harmonic guided wave is equal to two times the propagation constant of the fundamental guided wave, efficient SHG can be achieved.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 61% of the total text.

Page 1 of 2

XEROX DISCLOSURE JOURNAL

ACHIEVING EFFICIENT SHG IN THIN FILM

WAVE~

GUIDE THICKNESS
Robert D. Burnha~

Donald R. Scifres William Streifer Wolfgang Stutius

Proposed Classification

U.S. Cl. 331/94.5 D

mt. Cl. HOls 3/00

~ 32

By second harmonic generation (SHG), frequency doubling can be obtained from infrared diode laser sources to create visible photons, such as 4500A (blue) photons. In such devices, the laser, such as DFB laser, is optically coupled to a thin film waveguide in which the frequency doubling takes place. By accurately controlling the thickness of the waveguide to a predetermined value so that the propagation constants of the generated second harmonic guided wave is equal to two times the propagation constant of the fundamental guided wave, efficient SHG can be achieved.

Since it is very difficult to fabricate the precise thickness desired in such a waveguide, the proper thickness can be accurately obtained by ion milling after waveguide fabrication. The milling apparatus 10 for this purpose comprises ion milling chamber 12 having an ion gun source 14. An inert gase environment, such as argon, is provided in chamber 12.

The gas laser source 16 of frequency f is directed through the optical window 18 into chamber 12, A prism 20 is used to couple the laser light into the optical thin film waveguide 22 supported on substrate 24. The light propagates down waveguide 22 and generates light of frequency 2f,

Volume 4 Number 3 May/lune 1979 349

[This page contai...