摘要:

Integration of an intensity light modulator and a LOC‐DBR laser on a single chip has been demonstrated. The injection‐type modulator gives a variable loss (or gain) to the laser light, coupled to it via an interconnecting waveguide, and thus modulates its intensity in accordance with the injected current of the modulator. An extinction ratio of more than 10 was obtained.

ISSN:0003-6951    

DOI:10.1063/1.90033

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Sodium vapor seeded into a hypersonic helium flow through an orifice on a model is used as a tracer to determine velocity profiles. A narrow‐linewidth tunable dye laser is scanned across the Doppler‐shifted absorption line of the sodium and the resonant fluorescence is observed. Curves showing the velocity‐shifted pressure‐ and temperature‐broadened absorption lines at several points in the flow are presented. Fluorescence is strong enough to use this technique for quantitative flow visualization: at each laser frequency, a specific velocity component is highlighted and easily observed by eye.

ISSN:0003-6951    

DOI:10.1063/1.90034

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A new class of bistable optical devices is described which do not require resonators or single‐mode lasers. Optical bistability was demonstrated using a LiNbO3electro‐optic modulator and a multimode laser.

ISSN:0003-6951    

DOI:10.1063/1.90035

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

The saturation behavior of the spontaneous emission intensity from a transverse‐mode stabilized (GaAl)As laser is studied. The spatial hole burning is observed from the top surface of the laser, and a complete gain saturation is confirmed to occur in the lasing region.

ISSN:0003-6951    

DOI:10.1063/1.90036

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

P‐doped germanium and broadband gas absorbers have been used to increase significantly the energy output of the power amplifiers in the LASL Eight‐Beam CO2Laser System. Because they are less easily damaged, gas absorbers are preferred for this application.

ISSN:0003-6951    

DOI:10.1063/1.90037

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Rates for the recombination processesX++F−+X→XF*+X, (X≡He, Ne, Ar, Kr, Xe) at 300 K are calculated for pressures of the background gasXin the range ∼0.1–50 atm. Rates as high as (2–7) ×10−6cm3 sec−1are obtained for pressures 1–5 atm of Xe→He, and in general decrease with increasing ionic mass, except at low gas densities.

ISSN:0003-6951    

DOI:10.1063/1.90038

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

Amorphous and uniform silicon nitride films with thicknesses of less than 100 A˚ have been thermally grown on silicon wafers by employing purified ammonia gas. The films are much denser than conventional CVD Si3N4films. The MNS (metal‐thermal nitride‐silicon) structures have very lowNssin the order of 3×1010cm−2eV−1and an effective electron mobility of larger than 800 cm2/V sec in the fabricatedn‐channel MNSFFT.

ISSN:0003-6951    

DOI:10.1063/1.90039

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A new method of fabricating gallium arsenide MOS devices with improved electrical properties is discussed. The device consists of a gallium arsenide substrate overlaid with a gallium arsenic oxide, a thin aluminum oxide, and a metallic contact. The oxide layers are fabricated using a plasma oxidizing process. These MOS devices show very high breakdown voltages (typically ≈±4×106V/cm) and have low surface‐state densities (≈5×1010cm−2).

ISSN:0003-6951    

DOI:10.1063/1.90040

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A technique is described for measuring the density and energy distribution of surface states at the Si‐SiO2interface in MNOS capacitors. The effects of charge injection into the insulator are taken into account by making use of a fast voltage ramp to monitor the instantaneous values of the surface potential during a quasistatic capacitance‐voltage sweep. The technique has been used to investigate the effect of charges trapped in the nitride on the interface‐state density.

ISSN:0003-6951    

DOI:10.1063/1.90041

出版商:AIP    

年代:1978

数据来源: AIP

摘要:

A simple analytical expression is derived for charge retention in MNOS memory devices assuming that retention loss is limited by Frenkel‐Poole release from monoenergetic traps. This model shows that charge retention becomes eventually independent of the initial charge distribution. Experimental data obtained at elevated temperatures confirm this model and provide a trap depth of 1.5 eV, Frenkel‐Poole coefficient of about 6×10−4cm1/2 V−1/2 eV, and effective escape attempt rate factor of 1.2×108sec−1.

ISSN:0003-6951    

DOI:10.1063/1.90014

出版商:AIP    

年代:1978

数据来源: AIP