US 4,309,668 AGranted

Stripe-geometry double heterojunction laser device

AssigneeNippon Electric Co., Ltd.

InventorsMasayasu Ueno, Hiroo Yonezu, Roy Lang

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Abstract

A stripe-shaped excitation region is provided in an active layer of a double heterojunction laser device, the excitation region and the other region of the active layer being endowed with an effective refractive index difference or optical absorption coefficient difference therebetween, and a carrier injection region is provided contiguously to the excitation region, whereby the laser device exhibits a low ohmic resistance, effects a stable lower-order transverse mode oscillation and suppresses relaxation oscillations. By preventing the stripe-shaped excitation region and the carrier injection region from being exposed to reflective surfaces, the aforecited beneficial results can be realized over a wide range of operating currents, and a laser device of extremely high power density emission is achieved due to the increase of the threshold of the catastrophic optical damage on mirrors.

Claims18

Dependent claims

A stripe-geometry heterostructure semiconductor laser comprising:

first and second ohmic contacts,
a multilayer active medium including a first epitaxial layer of Al.sub.x Ga.sub.1-x As, a second epitaxial layer of Al.sub.y Ga.sub.1-y As, 0.ltoreq.y.ltoreq.x, thereby forming a first heterojunction at the interface therebetween, and a third epitaxial layer of Al.sub.z Ga.sub.1-z As, z>y, thereby forming a second heterojunction at the interface between said Al.sub.z Ga.sub.1-z As layer and said Al.sub.y Ga.sub.1-y As layer, said medium having a pair of spaced parallel reflective surfaces forming a pair of mirrors of an optical resonator, said second layer including a first region extending between said reflective surfaces in a stripe-like manner with the ends thereof spaced apart from said reflective surfaces, and a second region contiguous to said first region and extending between said reflective surfaces and having a predetermined band gap, said first region having a band gap narrower than that of said second region, said third layer including a third region extending between said reflective surfaces so as to overlay said first region, the width of said third region being wider than that of said second region, said third region being adapted to inject carriers into said second layer.

Dependencies are inferred from the claim text.

Facts

Application: 06/014,012Filed 21 Feb 1979
Priority: JP 53-1888220 Feb 1978
Granted: 5 Jan 1982
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

H01S 5/16
Construction or shape of the optical resonator , e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or…:…
H01S 5/20
Semiconductor lasers: structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical…
H01S 5/2059
Methods of obtaining the confinement: by means of particular conductivity zones, e.g. obtained by particle bombardment or diffusion
H01S 5/22
Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or…:…