At&t Bell Laboratories

University of Texas System

Other

Picolight, Inc.

Dennis G Deppe

Erdmann F Schubert

George J Zydzik

Jack L Jewell

Leonard C Feldman

Russell Dean Dupuis

Kuochou Tai

Niloy K Dutta

Rose F Kopf

Li-Wei Tu

Thomas John Rogers

Kai-Feng Huang

Russell J Fischer

Oleg B Shchekin

Li Wei Tu

Diana L Huffaker

Solid-state optoelectronic and electronic devices that use semiconductor quantum dots for manipulation of photonic or electronic properties include a semiconductor active region forming a quantum dot heterostructure having a plurality of quantum dot layers each having discrete quantum hole states and a p-type impurity layer formed proximate to at least one of the quantum dot layers to provide excess equilibrium hole charge to occupy at least some of the discrete quantum hole states to improve To and other performance characteristics of quantum dot devices.

Optoelectronic and electronic devices based on quantum dots having proximity-placed acceptor impurities, and methods therefor

Disclosed is a low threshold vertical cavity surface emitter having a low refraction index confining layer ( ) directly in the cavity spacer. This allows a &frac12; wavelength cavity spacer and lateral size of as low as 2 &mgr;m. Also disclosed is a method of rapid temperature annealing to seal a III-V crystal and inhibit oxidative degradation.

Low threshold microcavity light emitter

An improved aperture is provided. The aperture comprises: at least a first layer; the first layer being oxidized in a laterally oriented first region; the first layer being modified within a laterally oriented second region, the second region being oxidized less than the first region; a second layer disposed above the first layer, the second layer being oxidized less than the first layer and providing material to modify the laterally oriented second region and thereby define an aperture. Additionally, a method for producing the aperture is disclosed.

Semiconductor device having an oxide defined aperture

This invention embodies a Vertical Cavity Surface Emitting Laser with a top mirror comprising at least one pair of quarterwave layers, each pair consisting of a low index of refraction layer and a high index of refraction layer, the high index of refraction layer being a semiconductor chosen from GaP and ZnS and the low index of refraction layer being chosen from borosilicate glass (BSG) CaF.sub.2,MgF.sub.2 and NaF. Especially useful in vertical cavity surface emitting lasers are mirrors formed by a stack of a plurality of pairs of GaP/BSG or ZnS/CdF.sub.2. Such mirrors have a high reflectivity characteristics required for an efficient operation of the laser. The GaP/BSG or ZnS/CaF.sub.2 mirror structure represents a considerable improvement over previous designs for VCSELs in terms of ultimate reflectivity, low loss, and post growth processing compatibility.

Optical devices with electron-beam evaporated multilayer mirror

In the present invention, spontaneous photon emission intensity in a semiconductor quantum well is strongly influenced by a highly reflecting interface, with the quantum well to interface spacing being less than the optical emission wavelength of the quantum well. An enhancement/inhibition ratio on the order of 10 is possible according to the present invention using a single reflector, and enhancement/inhibition ratios on the order of 1000 are possible when two reflectors are used in the quantum well light-emitting diode structures. In addition, according to the present invention, the gain, directionality, and efficiency of a vertical cavity surface-emitting laser can also be greatly improved. A method of making a device according to the present invention is also presented.

Quantum well device with control of spontaneous photon emission, and

This invention is a semiconductor vertical cavity surface emitting laser comprising a lasing cavity with an active layer, a bottom (rear) mirror and a top (front) mirror, and a front and rear electrodes for applying excitation current in direction substantially parallel to the direction of optical propagation. In accordance with this invention the front mirror comprises a thin, semitransparent metal layer which also acts as the front electrode. The metal layer is upon a highly doped layer forming a non-alloyed ohmic contact. The metal is selected from Ag and Al and is deposited in thickness ranging from 5 to 55 nm. The VCSEL is a semiconductor device wherein the semiconductor material is a III-V or II-VI compound semiconductor. For a VCSEL with GaAs active layer, the light output from the front metal mirror/electrode side yields a high external differential quantum efficiency as high as 54 percent. This is the highest quantum efficiency obtained in VCSEL structures. Quantum efficiencies on the oder of 10 to 30 percent are typical for prior art VCSEL structures. The VCSEL is suitable for fabrication utilizing planar technology.

Vertical cavity surface emitting lasers with electrically conducting

In a vertical cavity laser, such as an InP based vertical laser, the energy bandgap in the active region can be made equal to or larger than the bandgap in a semiconductor mirror stack by virtue of degenerate doping in the stack sufficient to suppress electronic band-to-band optical absorption. For example, the active region of an InP based laser can be lattice-matched GaInAs, GaInAsP, or a multiple quantum well structure composed of layers of InP and GaInAs--with the mirror stack composed of alternating layers of InP and degenerately doped n-type lattice-matched GaInAs or GaInAsP.

Vertical cavity semiconductor lasers

An electrically pumped vertical cavity laser depends upon reflection as between an unaided DBR reflector on one side of the cavity and a metal-supplemented DBR reflector on the other. Placement of the shorter supplemented DBR on the p-conductivity type side of the cavity reduces the resistance of the electrical series pump path. Permitted use of an active region of a thickness of 1 .mu.m or less in the lasing direction results in low lasing threshold. The structural approach is of significance for laser integration in integrated circuits, whether electro-optic or all-optic.

Growing community of inventors

Austin, TX, United States of America

Dennis G Deppe