摘要:

We describe a new type of optical frequency translator which utilizes Bragg diffraction from a traveling index wave produced by an interdigitated electrode grating on a LiNbO3surface waveguide. The grating is driven by a three‐phase electrical signal that results in a unidirectional wave with a fixed Bragg angle determined by the electrode spacing. The diffraction thus produces a single‐sideband suppressed carrier optical output. Measurements at 10 and 100 MHz have yielded greater than 90% carrier‐to‐sideband conversion efficiency with over 100:1 suppression of the carrier and unwanted sideband. The device should be operable from arbitrarily low frequencies up to several gigahertz.

ISSN:0003-6951    

DOI:10.1063/1.94090

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Data are presented showing that it is possible to photopump and operate a quantum well heterostructure laser at equivalent current densities (Jeq) as low as 70 A/cm2. Continuous 300‐K laser operation of a single 60‐A˚ GaAs (x=0) quantum well in the center of a ∼0.12‐&mgr;m‐thickx′∼0.30 Alx′Ga1−x′As waveguide (and carrier reservoir), which is confined byx″∼0.85 Alx″Ga1−x″As layers, is demonstrated atIeq∼0.4 mA (168 W/cm2,Jeq∼70 A/cm2). These quantum well heterostructures are grown by organometallic vapor phase epitaxy.

ISSN:0003-6951    

DOI:10.1063/1.94091

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A theoretical investigation has been made of surface polariton reflection and radiation at the end face of a metal slab. Dielectric materials of dielectric constants &egr;dand &egr;′dlie above and beyond the end of the metal slab, respectively. Energy transmission and reflection coefficients have been calculated for a surface polariton incident on the end face of the metal slab for various slab thicknesses when &egr;d=&egr;d=1 and &ohgr;p/&ohgr;=4. The energy reflection coefficient has also been investigated as a function of &egr;dwith &egr;′d=1. The angular distribution of the radiation pattern has also been studied for two different &egr;d.

ISSN:0003-6951    

DOI:10.1063/1.94092

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The effect of various rare‐gas diluents on the operating performance of thee‐beam‐excited XeCl laser is theoretically analyzed. The analysis of the XeCl* pumping process and the extraction process could solve the dependence of the intrinsic efficiency, small‐signal gain, and absorption on the rare‐gas diluent. As a result, there is no appreciable difference in the intrinsic efficiency between the Ar‐based and the Ne‐based mixtures. Selecting the optimum excitation parameters, the highest intrinsic efficiency of 5% is achieved for both diluents. Although the highest small‐signal gain is achieved without a diluent gas, the extraction efficiency is reduced and the intrinsic efficiency is small due to the large amount of three‐body collisional quenching.

ISSN:0003-6951    

DOI:10.1063/1.94093

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

We have directly determined a high velocity (v=2×107cm/s) for electrons in a submicron (0.42 &mgr;m), strongly graded (quasifieldF=8.8 kV/cm) highly doped ( p=4×1018cm−3) AlxGa1−xAs layer. A transit time of only 1.7 ps was measured (an order of magnitude shorter than that forF=1.2 kV/cm). Such a structure would be ideal for the low resistance base of a high‐speedn‐p‐ntransistor.

ISSN:0003-6951    

DOI:10.1063/1.94094

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

In this letter we report on a novel method to passively mode lock a semiconductor laser. We present experimental results of GaAlAs buried heterostructure semiconductor laser with a split contact coupled to an external cavity. The split contact structure is used to introduce a controllable amount of saturable absorption which is necessary to initiate passive mode locking. Unlike previous passive mode locking techniques, the method presented does not rely on absorption introduced by damaging the crystal and is consequently inherently more reliable. We have obtained pulses with a full width at half‐maximum of 35 ps at repetition frequencies between 500 MHz and 1.5 GHz.

ISSN:0003-6951    

DOI:10.1063/1.94095

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Stimulated emission of near‐band‐gap radiation is observed in the semimagnetic semiconductor Cd1−xMnxSe,x=0.1. Excitation was achieved by optical pumping just below the absorption edge. The photon energy of the recombination emission is a strong function of both magnetic field and temperature. With increasing field, the emission shifts to lower energy. The shift is primarily proportional to the Mn++magnetization and at high fields saturates at approximately 60 meV. The magnitude is in reasonable agreement with that expected from the exchange energies.

ISSN:0003-6951    

DOI:10.1063/1.94083

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A narrow linewidth (&Dgr;&lgr;=0.0004 A˚) modular dye laser system has been constructed and used to investigate the gain characteristics of a XeCl* oscillator. When operated as a free‐running oscillator lasing occurred simultaneously on theBv=0→Xv=1andBv=0→Xv=2transitions. The injection of 20 &mgr;J of UV radiation from the dye chain was sufficient to confine the entire output to either one of these two transitions. A measured linewidth of 0.0004 A˚ was obtained at average power levels of up to 5 W.

ISSN:0003-6951    

DOI:10.1063/1.94084

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Graphical solutions and experimental results of the blocking oscillation of the guided‐wave optical bistable devices using dc drift phenomena of LiNbO3are reported. The frequency of the oscillation can be varied in the range from 0.1 to 100 Hz by changing biasing voltage and input light level.

ISSN:0003-6951    

DOI:10.1063/1.94085

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A 100‐MeV32S beam was used to pump a He‐Ar gas laser. Laser action of the 1.79‐&mgr;m line was observed above a threshold of 33‐W beam power input. The light conversion efficiency is about 1×10−4with a (99%)He‐(1%)Ar gas mixture at 200‐mbar pressure and 132‐W input power.

ISSN:0003-6951    

DOI:10.1063/1.94086

出版商:AIP    

年代:1983

数据来源: AIP