摘要:

The field control of the luminescent characteristics is investigated with three‐terminal field‐effect light‐emitting devices with superlattice buffer layers, showing a high‐speed switching (∼0.8 ns) of emission intensity, free from lifetime limitation at room temperature and a high quantum yield of the emission intensity, i.e., an external efficiency &eegr;ex≥1%. It is demonstrated that a combination of the field control of radiative lifetime with carrier leakage results in a high‐speed modulation of luminescence intensity under a fixed carrier population in the active layer, unchanged with and without electric fields.

ISSN:0003-6951    

DOI:10.1063/1.102992

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

Optical bistabilities due to electronic refractive index changes are observed in an InGaAs/InAlAs multiple quantum well e´talon device at around 1.5 &mgr;m wavelength. The switching speeds of less than 30 ns and the induced refractive index changes of −0.1% are observed using a tunableF‐center laser.

ISSN:0003-6951    

DOI:10.1063/1.102973

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

A simple and highly reliable package consisting of a 1‐cm‐long AlGaAs laser diode array mounted directly on a silicon microchannel cooler has been demonstrated. 3.4×109shots were logged on this device at an average optical output of 8.75 W with only a 6% increase in current required to hold the light output constant. This extrapolates to a current doubling lifetime of 1.6×1011shots. The thermal impedance was also measured to be 0.014 °C/(W/cm2).

ISSN:0003-6951    

DOI:10.1063/1.103192

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

A monolithic grating‐surface‐emitting ring laser has been fabricated and its spectral properties and far‐field radiation pattern studied. The ring laser was configured from two columns of two‐dimensional grating‐surface‐emitting diode laser arrays. The columns were optically linked at each end with total‐internal‐reflection corner turning mirrors formed by micromachining grooves in the wafer with a focused ion beam. Single longitudinal mode operation with a high degree of spatial coherence between the two columns and a narrowing of the lateral far‐field pattern were observed.

ISSN:0003-6951    

DOI:10.1063/1.102974

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

A monolithic KNbO3resonant cavity was used to generate 455 nm radiation by sum frequency mixing of a 1064 nm Nd:YAG laser with resonantly enhanced 795 nm emission of a diffraction‐limited externally injection‐locked GaAlAs broad‐stripe laser diode. Blue output of 154 mW was measured with 4.5 W of 1064 nm and 240 mW of 795 nm radiation in quasi‐cw operation.

ISSN:0003-6951    

DOI:10.1063/1.102975

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

A large single crystal (18×40×15 mm3) of a new nonlinear optical material ‘‘chalcone derivative’’ has been grown by an evaporation method. This crystal was relatively easy to grow to a large size and was chemically stable. The cutoff wavelength was 430 nm. The calculated phase matching angles for the second‐harmonic generation (SHG) of Nd:YAG lasers agreed with the experimental data. Effective nonlinear optical coefficientsdeffof type I and type II for SHG have been measured to be 3.5 pm/V for type I and 5.7 pm/V for type II.

ISSN:0003-6951    

DOI:10.1063/1.102976

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

We present the results of low‐temperature photoluminescence and stimulated emission experiments performed on a CdTe/Hg0.45Cd0.55Te/Hg0.67Cd0.33Te multiquantum well separate confinement heterostructure grown by molecular beam epitaxy. The photoluminescence results suggest that because of the growth conditions, there is a strong interdiffusion in the multiquantum well region. Pulsed stimulated emission was observed from this structure up to 77 K.

ISSN:0003-6951    

DOI:10.1063/1.102977

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

Preliminary experimental results are reported on two‐wavelength switching in a GaAs‐based multiple quantum well planar directional coupler. It is verified that a novel design of the multiple quantum well (MQW) coupling region leads to a wavelength multiplexing/demultiplexing/switching operation. It is shown that control of such a function can be exercised by either the wavelength of operation or by an applied electrical voltage through exciton resonance effects in the MQW layer. The layer structure exhibits two exciton‐resonance peaks at which wavelength‐selective switching can be achieved.

ISSN:0003-6951    

DOI:10.1063/1.102978

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

The carrier recombination rate in GaAs‐AlGaAs single quantum well layers is investigated using a small‐signal technique for carrier densities from 1017to 1019/cm3. For carrier densities up to mid 1018/cm3, the inverse of the differential carrier lifetime, 1/&tgr;d, increases linearly with the carrier density. The differential rate, however, saturates at higher carrier densities and remains nearly constant for carrier densities higher than 1019/cm3. The deviation from the bulk recombination behavior is due to a portion of the injected carriers populating the semicontinuum states where the rate for the radiative transition is much smaller. The experimental data indicate that the runaway increase of threshold current with decreasing cavity length commonly observed in the short‐cavity lasers is mainly due to the loss of carrier confinement at high carrier densities rather than due to fast carrier‐depleting processes, such as Auger recombination.

ISSN:0003-6951    

DOI:10.1063/1.102979

出版商:AIP    

年代:1990

数据来源: AIP

摘要:

A frequency sweeping (chirping) mechanism governed by the lasing gas pressure and composition has been observed in a long‐pulse TE CO2laser for the first time. The mechanism was detected in heterodyned data obtained from photomixing the pulsed laser output with a cw local oscillator. A theory has been developed which links this chirp‐governing mechanism to the vibration‐translation (V‐T) transfer rate from the lower laser level to the ground state. This new theory extends the existing theories on chirp in pulsed CO2lasers into the long‐pulse regime.

ISSN:0003-6951    

DOI:10.1063/1.102980

出版商:AIP    

年代:1990

数据来源: AIP