摘要:

We demonstrate the reduction of the spectral linewidth in AlGaAs/GaAs distributed feedback lasers by a multiple quantum well structure for the first time. The spectral linewidth‐output power product was 54 MHz mW and was eight times smaller than that of conventional double heterostructure distributed feedback lasers. The narrowest spectral linewidth was 10.5 MHz at 5 mW.

ISSN:0003-6951    

DOI:10.1063/1.98014

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Layer intermixing in GaAs‐AlGaAs superlattices achieved by Zn thermal diffusion has been used to fabricate buried channel optical waveguides. Linear waveguides with small, abrupt bends were made and light was seen to be transmitted through these for bend angles up to 7.5 degrees corresponding to an effective index of refraction difference of 0.9% for a 50% average Al composition of the layers bounding the superlattice. For radiation between the band gap of bulk GaAs (870 nm) and the effective band gap of a 10‐nm GaAs quantum well (840 nm), the 3‐mm‐long waveguides appeared to be semitransparent suggesting a possible use in planar, buried channel all‐semiconductor integrated optoelectronics.

ISSN:0003-6951    

DOI:10.1063/1.98015

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Broad area, conventional double heterostructure lasers were fabricated by metalorganic chemical vapor deposition. Continuous wave output power level of 710 mW and stable, single‐lobed far‐field patterns with a beam divergence as narrow as 2.1° (2.2 times diffraction limit) at 50 mW and 2.9° at 200 mW for a 50‐&mgr;m‐wide laser were obtained.

ISSN:0003-6951    

DOI:10.1063/1.98016

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The surface plasmon polariton is used to investigate the nematic director reorientation close to the director aligning layer. This has resulted in the determination of the surface anchoring energy and the realization that surface effects are significant even when surface anchoring is strong. A consequence of this is that existing data for the physical parameters of the nematic material may suffer systematic errors.

ISSN:0003-6951    

DOI:10.1063/1.98017

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

A double heterostructure InGaAsP/InP mesa laser and a mass transport laser were integrated vertically with an InGaAsP/InP double heterojunction bipolar transistor, resulting in the first realization of laser operation in a vertical integration. Laser thresholds as low as 17 mA and an output laser power of over 30 mW were observed. A new type of bistable laser and electro‐optical switching were demonstrated.

ISSN:0003-6951    

DOI:10.1063/1.98018

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

A diode‐laser array model, solving the two‐dimensional Laplace equation in the passive layer and the carrier diffusion equation in the active layer in a self‐consistent manner, is presented. The model is general and does not make use of the usual one‐dimensional approximation to the current spreading problem. The beam‐propagation method used in solving the wave equation eases the inclusion of any axial variations.

ISSN:0003-6951    

DOI:10.1063/1.98019

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

We have obtained coherent operation of multiple pulsed dye oscillators by using a single phase conjugate mirror as a common end mirror for up to three physically distinct cavities. The phase conjugate mirror operates via the photorefractive effect in a crystal of BaTiO3, through a four‐wave mixing process that requires no external pumping beams. The system has been operated in both a narrow‐band (0.05 nm) and a broadband (0.25 nm) configuration.

ISSN:0003-6951    

DOI:10.1063/1.98020

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

A longitudinal discharge XeCl 308‐nm excimer laser operated with automatic spark UV preionization is reported. Laser oscillation has been obtained using a four‐segmented longitudinal discharge tube of 260 mm length and 4 mm inner diameter and employing a capacitor transfer circuit with commercially available doorknob ceramic capacitors. Spark UV preionization has been found to increase the laser output energy.

ISSN:0003-6951    

DOI:10.1063/1.98021

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

We report the ultrafast operation of a light‐controlled optical‐fiber modulator, driven by subpicosecond, compressed, and amplified (6000 A˚) dye laser pulses, controlling frequency‐doubled (5320 A˚) yttrium aluminum garnet laser pulses. The operation of the modulator is based on the optical Kerr effect, and its main component is 7 mm of single‐mode optical fiber. Using this system as a light‐controlled shutter, we produced either 0.4 ps green light pulses or 0.5 ps holes on the much longer duration second harmonic pulses.

ISSN:0003-6951    

DOI:10.1063/1.98022

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Effects of a pressurized spark switch on N2laser output have been observed optically with quartz fibers. The output power increased with decreasing the gap of the spark switch while keepingpgd=0.51 kg/cm (pgis the N2gas pressure in the spark switch anddis the gap distance) andpN2=40 Torr (pN2is the pressure of the laser medium gas). One nanosecond pulses with peak powers of 120 kW have been generated for the first time for low‐pressure operating N2lasers.

ISSN:0003-6951    

DOI:10.1063/1.98023

出版商:AIP    

年代:1987

数据来源: AIP