摘要:

Wide‐band tuning of a XeF (C→A) excimer laser pumped with a longitudinal electron beam was demonstrated from 455 to 529 nm. The spectral linewidth of the laser emission was ∼5 nm when a prism was used as a wavelength selecting element, and narrowed to ∼1 nm when the prism was replaced by a diffraction grating.

ISSN:0003-6951    

DOI:10.1063/1.92740

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Lasing on several transitions of theB2J→X2Jband of zinc‐iodide (ZnI) with wavelengths ranging from 600 to 604 nm has been demonstrated. Pumped by the dissociative excitation of ZnI2(using an ArF excimer laser), this laser exhibits many of the optical and chemical properties of the HgBr2blue‐green dissociation laser.

ISSN:0003-6951    

DOI:10.1063/1.92741

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A direct measurement of laser beam steering resulting from anomalous dispersion in an absorbing medium was achieved with the use of a sensitive wavefront sensor. The experimental setup, which includes a Brewster’s angle absorption cell, a continuous‐wave, frequency‐scannable hydrogen flouride (HF) chemical laser, an acousto‐optical modulator and phase demodulator, and servo‐ and detection‐ electronics, is described. The experimental results provided a direct measure of the anomalous dispersion for HF [P1(6) line] that agrees within about 10% with the value deduced from an absorption measurement.

ISSN:0003-6951    

DOI:10.1063/1.92742

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Proton bombardment at 3×1015–1016‐cm−2dosage level and 300 keV has been used to introduce a ∼4‐&mgr;m‐long nonradiative region at one of the mirror facets. The region acts as a saturable absorber and converts the initially temporally stable optical emission to a pulsating behavior with a repetition rate in the 0.5–3‐GHz range.

ISSN:0003-6951    

DOI:10.1063/1.92743

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A self‐sustained oscillation of laser light intensity emitted by a laser diode was newly observed by a delayed network using an optical fiber and an electrical feedback system. The time delay (transit time) of the light beam through the optical fiber plus the time delay of the electrical signal in the electrical feedback system determines the oscillation frequency of the light intensity. The oscillation for the fiber length of 7 km was obtained by using an electrical amplifier with large gain. With a wide‐band amplifier, harmonic (multimode) oscillations took place where the waveform was almost square.

ISSN:0003-6951    

DOI:10.1063/1.92744

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Experimental results of a buried heterostructure cw laser with a controllable amount of saturable absorption introduced by a segmented contact are presented. With no absorption the laser is stable and has a linear output characteristic. Increasing of the saturable absorption by changing the pump current through the control segment causes the light output of the device to pulsate and to show bistable and hysteretical behavior. The introduction of a controllable amount of saturable absorption suggest the usefulness of this device in generating extremely short pulses, for example, by passive mode locking and as a bistable optical device.

ISSN:0003-6951    

DOI:10.1063/1.92745

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Multiplication of the frequency shift of a tunable solid‐state laser is achieved via resonant pumping in a double‐doped rare‐earth crystal. With a tuning shift of only 0.6 nm of the pump, an output shift of 100 nm is achieved.

ISSN:0003-6951    

DOI:10.1063/1.92746

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A method of quasidirect profiling of impact excitation of electroluminescence in a metal semiconductor junction utilizing the Auger quenching of a localized center luminescence by either free or weakly bound electrons is described. Experimental results obtained on CdF2:Mn,Y Schottky diodes unambiguously prove a spatial separation of the acceleration and collision excitation processes in high‐field electroluminescence.

ISSN:0003-6951    

DOI:10.1063/1.92739

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The various interpretations of turn‐on delay in semiconductor laser diodes are critically reviewed. It is concluded that values for the total carrier lifetime, or radiative coefficient, cannot be deduced unambiguously from laser turn‐on delay measurements alone. However, using additional luminescence efficiency measurements in the spontaneous regime, both the radiative coefficient as well as the nonradiative lifetime can be calculated. The average value for the radiative coefficient in GaAs obtained in this way is 1.3×10−10cm3/s.

ISSN:0003-6951    

DOI:10.1063/1.92747

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The influence on the photoacoustic signal of the thermal contact resistance at the interface sample substrate is investigated using a thin metallic foil (thickness ∼12.5 &mgr;m) as sample. The foil is either applied by pressure against the substrate or epoxyed on it. The resistance is determined by interpreting magnitude and phase data obtained by varying the laser source modulation frequency. In the light of the results obtained with the thin foil, we discuss the limitations introduced by thermal contact in the photoacoustic detection of aerosols collected on a surface.

ISSN:0003-6951    

DOI:10.1063/1.92748

出版商:AIP    

年代:1981

数据来源: AIP