摘要:

A new experimental method to study modal interaction in semiconductor lasers is presented. The inter‐intramode correlation spectroscopy investigates correlations between intensity and phase fluctuations having their origin in different longitudinal modes. First results for GaAs/(GaAl)As multimode lasers reveal correlated frequency fluctuations of the total longitudinal mode comb. Refractive index fluctuations and intermode coupling are discussed as the origin for these intramodal fluctuations.

ISSN:0003-6951    

DOI:10.1063/1.96948

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The interaction of a dense (n∼1012cm−3), mildly relativistic (1.8<&ggr;<3) electron beam and a cylindrical, dielectric lined waveguide has produced tunable microwave radiation in the 150–310 GHz frequency range with an estimated power output of 500 kW at 150 GHz and 10 kW at 310 GHz. The measured output frequency agrees well with the frequency for which the phase velocity of the TM01mode of the dielectric lined guide is synchronous with the electron beam velocity.

ISSN:0003-6951    

DOI:10.1063/1.96949

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The propagation loss is canceled, and 5 dB of net gain is obtained by Brillouin amplification in a 37.5‐km‐long single‐mode optical fiber. A narrow linewidth external cavity semiconductor laser is used as the pump source and a gain of 4.3 dB/mW pump power is measured. The Brillouin linewidth is measured to be 150 MHz in contrast to previous measurements of ∼20 MHz. The Brillouin Stokes shift was 11.3 GHz at 1.5 &mgr;m wavelength.

ISSN:0003-6951    

DOI:10.1063/1.96950

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A traveling‐wave amplifier has been fabricated from a ten‐stripe, AlGaAs phase‐locked injection laser array by antireflection coating both facets. A small‐signal gain of 18.6 dB, when corrected for optical coupling efficiency, has been observed, resulting in over 100 mW of coherent optical power output. When the signal source is a single transverse and single longitudinal mode diode laser, the far‐field radiation pattern is dominated by a single lobe with a divergence of 0.86° in the lateral plane.

ISSN:0003-6951    

DOI:10.1063/1.96951

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We present a simple model which may be used to evaluate the suitability of different ions for rapid plasma cooling by line radiation in recombination pumped x‐ray laser schemes.

ISSN:0003-6951    

DOI:10.1063/1.96952

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Graded barrier quantum well heterostructures have been grown by metalorganic chemical vapor deposition and processed into real index‐guided shallow mesa laser arrays. Single‐stripe devices have threshold currents as low as 14 mA (533 &mgr;m length) and ten‐element arrays have threshold currents as low as 9 mA per stripe with 52% differential quantum efficiency. These arrays operate phase locked with sharp double‐lobed far‐field patterns up to 1.75 times threshold current.

ISSN:0003-6951    

DOI:10.1063/1.96953

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Corrections to the rate equation approximation are derived and applied to a semiconductor laser. Whereas these corrections do not affect the operating point of the device, they do alter the dynamic operation. To first order the correction produces a renormalization of familiar dynamic parameters. This renormalization, in turn, leads to a 20% correction to the field spectrum linewidth formula.

ISSN:0003-6951    

DOI:10.1063/1.96954

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We report the first parallel operation of GaAs optical logic elements and bistable devices. Arrays up to 2×4 in size were operated using a picosecond pump and probe technique, while in the bistable mode we achieved uniform response in two spots. Crosstalk due to carrier diffusion became noticeable at separations of typically ∼20–30 &mgr;m in the bistable devices. Pulsed operation at 82 MHz allowed separations down to ∼10 &mgr;m limited only by diffraction. Efficient heat sinking in the pulsed array resulted in negligible heating even when continually operated for many minutes. All experiments were performed at room temperature.

ISSN:0003-6951    

DOI:10.1063/1.96955

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The optical absorption coefficient of Ti:Al2O3samples at 490 nm for the &pgr; polarization (E∥cˆ) is found to be proportional to the concentration of Ti3+ions, as determined by measurement of the paramagnetic moment as a function of temperature and magnetic field. The experimental data yield the value &sgr;=(9.3±1.0)×10−20cm2for the absorption cross section of Ti3+, the active ion in the tunable Ti:Al2O3laser, at the peak of the laser pump band.

ISSN:0003-6951    

DOI:10.1063/1.96904

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A mixture of commercially available carbon black powders and hydrogen uranyl phosphate (HUP) precipitate can be used as the electrode material for miniaturized double‐layer capacitors. A solid cell of C‐HUP‖HUP‖C‐HUP has a capacitance of 1 F which, given the device area and thickness of 0.8 cm2and 0.2 cm respectively, corresponds to an energy density of more than 5 J/cm3. The charge×voltage factor is higher than 5×10−6s and the working voltage is over 1.6 V. The leakage current is lower than 3 &mgr;A at room temperature. The electrolyte can be operated up to about 120 °C if the device is hermetically sealed.

ISSN:0003-6951    

DOI:10.1063/1.96905

出版商:AIP    

年代:1986

数据来源: AIP