Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

TRANSVERSE MODE FILTERING

IP.com Disclosure Number: IPCOM000024007D
Original Publication Date: 1979-Jun-30
Included in the Prior Art Database: 2004-Apr-01
Document File: 2 page(s) / 380K

Publishing Venue

Xerox Disclosure Journal

Abstract

One manner of providing transverse mode control in a double heterostructure (DH) diode laser is to change the composition of one or more layers of the structure along the plane of the p-n junction. By changing the layer composition, a lateral refractive index profile is, in effect, created. The effective index of refraction is made greater between the dotted lines of DI-I laser shown in the figure. In the pumped area of the DH laser, losses along the plane of the p-n junction are greater for higher order transverse modes, The higher order modes have a higher threshold and do not oscillate.

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 55% of the total text.

Page 1 of 2

XEROX DISCLOSURE JOURNAL

TRANSVERSE MODE FILTERING Robert D. Burnham
Donald R. Scifres
William Streifer

Proposed Classification
U.S. Cl. 331/94.5 H

mt. Cl. H01s 3/00

~-OXIDE STRIFE ~ OR

  Go~ 1-pATpA~ _P~Goj~XAIXA5~

P-Go~yAly AS 2

-fl~G~ 1~AIZAS

-fl-Go~A5

22ME TALI~ATION

One manner of providing transverse mode control in a double heterostructure (DH) diode laser is to change the composition of one or more layers of the structure along the plane of the p-n junction. By changing the layer composition, a lateral refractive index profile is, in effect, created. The effective index of refraction is made greater between the dotted lines of DI-I laser shown in the figure. In the pumped area of the DH laser, losses along the plane of the p-n junction are greater for higher order transverse modes, The higher order modes have a higher threshold and do not oscillate.

The conventional DH laser consists of an active layer (7, 8, 9) with contiguous claddIng layers (4, 5, 6) and (10, 11, 12) of larger bandgap and lower refractive index. Layer (1, 2, 3) facilitates contact connection for laser operation. Layer (13, 14, 15) is the substrate upon which the other layers are grown by LPE, MBE or MOCVD. A current source is connected to the metalizations 20 and 22. The parameters for a typical DH laser are as follows:

Layer If Thickness

51, 2, 3 l.,um

Composition

Ga AlAs 0< p<O.l

'1~

4 5 6 7~/~/~9.

0 II 2 -

J

3 I 14 I 5

~1

5-~3OLI17l

Volume 4 Number 3 May/3une 1979 367

[This page contains 1 picture or other non-text object]

Page 2 of 2

TRANSVERSE MODE FILTERING (Cont~d)

4, 5, 6 l.5~m Ga

                          1 x~~xA50,15<x<0,8 7, 8, 9 0,1~tm Ga

1 ~AI~As O<yKO.3

10, 11, 12 1.5j~&m Gai ~Al~As 0.15<z~0.8

13, 14, 15 lOO

1um GaAs

The aluminum content in the regions 4 and 6 or in regions 7 and 9 or in reg...