MIXSELs - a new class of ultrafast semiconductor lasers

AbstractThe interband cascade lasers (IC) represent a new class of mid-IR light sources, which take advantage of the broken-gap alignment in type-II quantum wells to reuse electrons for sequential photon emissions from serially connected active regions. Here, we describe recent progress in InAs/GaInSb type-II IC lasers at emission wavelengths of 3.8-4 µm; these semiconductor lasers have exhibited significantly higher differential quantum efficiencies and peak powers than previously reported. Also, these lasers were able to operate at temperatures up to 217 K, which is higher than the previous record (182 K) for an IC laser at this wavelength. We observed from several devices at temperatures above 80 K a slope efficiency of ∼800 mW/A per facet, corresponding to a differential external quantum efficiency of /500%. A peak optical output power exceeding 4 W/facet and peak power efficiency of /7% were observed from a device at 80 K. Also, we report the first cw operation of IC lasers.

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ChemInform Abstract: Photochemistry of Tertiary Nitrosoalkanes in Solid Polymer Matrices: A Promising New Class of Organic Materials for Holographic Recording with Semiconductor Lasers.

ChemInform ◽

10.1002/chin.198806326 ◽

1988 ◽

Vol 19 (6) ◽

Author(s):

J. PINSL ◽

M. GEHRTZ ◽

A. REGGEL ◽

CHR. BRAEUCHLE

Keyword(s):

Semiconductor Lasers ◽

Organic Materials ◽

Polymer Matrices ◽

Solid Polymer ◽

Holographic Recording ◽

New Class

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Moving from ultrafast VECSELs to MIXSELs: a new class of ultrafast semiconductor lasers

10.1117/12.754533 ◽

2007 ◽

Author(s):

T. Südmeyer ◽

D. J. H. C. Maas ◽

A.-R. Bellancourt ◽

B. Rudin ◽

M. Golling ◽

...

Keyword(s):

Semiconductor Lasers ◽

New Class

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Structural aspects of silicon diffusion in quaternary III-V thin-film semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088567 ◽

1991 ◽

Vol 49 ◽

pp. 850-851

Author(s):

F. A. Ponce ◽

R. L. Thornton ◽

G. B. Anderson

Keyword(s):

Semiconductor Lasers ◽

Wide Bandgap ◽

Semiconductor Diode ◽

Visible Range ◽

P System ◽

Misfit Dislocations ◽

Lattice Match ◽

Semiconductor Diode Laser ◽

Thin Film Semiconductors ◽

Silicon Diffusion

The InGaAlP quaternary system allows the production of semiconductor lasers emitting light in the visible range of the spectrum. Recent advances in the visible semiconductor diode laser art have established the viability of diode structures with emission wavelengths comparable to the He-Ne gas laser. There has been much interest in the growth of wide bandgap quaternary thin films on GaAs, a substrate most commonly used in optoelectronic applications. There is particular interest in compositions which are lattice matched to GaAs, thus avoiding misfit dislocations which can be detrimental to the lifetime of these materials. As observed in Figure 1, the (AlxGa1-x)0.5In0.5P system has a very close lattice match to GaAs and is favored for these applications.In this work, we have studied the effect of silicon diffusion in GaAs/InGaAlP structures. Silicon diffusion in III-V semiconductor alloys has been found to have an disordering effect which is associated with removal of fine structures introduced during growth. Due to the variety of species available for interdiffusion, the disordering effect of silicon can have severe consequences on the lattice match at GaAs/InGaAlP interfaces.

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In Situ microscopy of the anodic etching of silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137537 ◽

1995 ◽

Vol 53 ◽

pp. 232-233

Author(s):

Frances M. Ross ◽

Peter C. Searson

Keyword(s):

Composite Structures ◽

High Surface ◽

High Surface Area ◽

Chemical Properties ◽

Selective Etching ◽

Silicon On Insulator ◽

Second Phase ◽

Porous Layers ◽

New Class ◽

Porous Semiconductors

Porous semiconductors represent a relatively new class of materials formed by the selective etching of a single or polycrystalline substrate. Although porous silicon has received considerable attention due to its novel optical properties1, porous layers can be formed in other semiconductors such as GaAs and GaP. These materials are characterised by very high surface area and by electrical, optical and chemical properties that may differ considerably from bulk. The properties depend on the pore morphology, which can be controlled by adjusting the processing conditions and the dopant concentration. A number of novel structures can be fabricated using selective etching. For example, self-supporting membranes can be made by growing pores through a wafer, films with modulated pore structure can be fabricated by varying the applied potential during growth, composite structures can be prepared by depositing a second phase into the pores and silicon-on-insulator structures can be formed by oxidising a buried porous layer. In all these applications the ability to grow nanostructures controllably is critical.

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The microtubule associated protein (MAP) tau forms a new class of triple-stranded left-hand helical fibrous protein polymer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123106 ◽

1992 ◽

Vol 50 (1) ◽

pp. 540-541

Author(s):

G. C. Ruben ◽

K. Iqbal ◽

I. Grundke-Iqbal ◽

H. Wisniewski ◽

T. L. Ciardelli ◽

...

Keyword(s):

Axial Ratio ◽

Normal Structure ◽

Paired Helical Filaments ◽

Left Hand ◽

New Class ◽

Protein Polymer ◽

Fibrous Protein ◽

Protein Map ◽

Neurotransmitter Transport ◽

Alzheimer Neurofibrillary Tangles

In neurons, the microtubule associated protein, tau, is found in the axons. Tau stabilizes the microtubules required for neurotransmitter transport to the axonal terminal. Since tau has been found in both Alzheimer neurofibrillary tangles (NFT) and in paired helical filaments (PHF), the study of tau's normal structure had to preceed TEM studies of NFT and PHF. The structure of tau was first studied by ultracentrifugation. This work suggested that it was a rod shaped molecule with an axial ratio of 20:1. More recently, paraciystals of phosphorylated and nonphosphoiylated tau have been reported. Phosphorylated tau was 90-95 nm in length and 3-6 nm in diameter where as nonphosphorylated tau was 69-75 nm in length. A shorter length of 30 nm was reported for undamaged tau indicating that it is an extremely flexible molecule. Tau was also studied in relation to microtubules, and its length was found to be 56.1±14.1 nm.

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Strain measurement in In0.2Ga0.8As/GaAs quantum wires by convergent beam electron diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138592 ◽

1995 ◽

Vol 53 ◽

pp. 444-445

Author(s):

S. Hillyard ◽

Y.-P. Chen ◽

J.D. Reed ◽

W.J. Schaff ◽

L.F. Eastman ◽

...

Keyword(s):

Electron Diffraction ◽

Semiconductor Lasers ◽

Quantum Wire ◽

Quantum Wires ◽

Convergent Beam Electron Diffraction ◽

Zero Order ◽

Beam Electron ◽

Local Lattice ◽

Device Applications ◽

Convergent Beam

The positions of high-order Laue zone (HOLZ) lines in the zero order disc of convergent beam electron diffraction (CBED) patterns are extremely sensitive to local lattice parameters. With proper care, these can be measured to a level of one part in 104 in nanometer sized areas. Recent upgrades to the Cornell UHV STEM have made energy filtered CBED possible with a slow scan CCD, and this technique has been applied to the measurement of strain in In0.2Ga0.8 As wires.Semiconductor quantum wire structures have attracted much interest for potential device applications. For example, semiconductor lasers with quantum wires should exhibit an improvement in performance over quantum well counterparts. Strained quantum wires are expected to have even better performance. However, not much is known about the true behavior of strain in actual structures, a parameter critical to their performance.

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