Browse Prior Art Database

Photon Recycled Injection Laser

IP.com Disclosure Number: IPCOM000080871D
Original Publication Date: 1974-Feb-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Stern, F: AUTHOR [+2]

Abstract

A conventional double heterostructure (DH) injection laser is modified so that a portion of the spontaneous emission spectrum within the laser cavity, which is above the lasing energy, is fed back into the active layer of the DH laser where it acts as a pumping source, along with the injected carriers of the injection laser.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Photon Recycled Injection Laser

A conventional double heterostructure (DH) injection laser is modified so that a portion of the spontaneous emission spectrum within the laser cavity, which is above the lasing energy, is fed back into the active layer of the DH laser where it acts as a pumping source, along with the injected carriers of the injection laser.

A conventional DH junction laser employs a 0.5 to 1.0 mu active region of GaAs, surrounded by a n-type GaAlAs on one side of the active region and n- type GaAs on the other side. Such DH junction is normally supported on a relatively thick layer of n-type GaAs, to which is applied an ohmic contact. The p- type GaAlAs does not readily accommodate an ohmic contact so a p-type GaAs is grown over the p-type GaAlAs, to permit the fabrication of an ohmic contact to the DH structure.

In the present teaching, the light-absorbing layers of n-type GaAs and p-type GaAs are removed and replaced with thin metallic reflectors, such reflectors serving not only as reflectors of spontaneously emitted light from the active region back into the active region where such light can further pump the GaAs laser cavity, but they also serve as electrodes for the DH structure. Such use of the normally wasted spontaneously emitted light as a pumping source, substantially reduces the threshold current of the DH injection laser. Additionally, by replacing GaAs with a metal reflector, the latter serves as a heat sink for the laser.

1