摘要:

We report an experimental investigation of the conversion efficiency of a frequency converter based on four‐wave mixing in semiconductor optical amplifiers. We find that the maximum of conversion efficiency has a nonlinear dependence on the unsaturated gain of the device. The observed features are explained by the presence of the Auger and bimolecular recombination. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114582

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Electro‐optical modulators based on intersubband transitions induced by normal‐incidence radiation in GaSb‐AlSb‐family asymmetric double quantum wells are proposed. An applied field transfers electrons from &Ggr;‐valley states in one well toL‐valley states in the other well, thereby radically altering the selection rules, resonance energies, and in‐plane effective masses. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114583

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

A phenomenon of voltage‐induced color‐selective absorption at metal/liquid crystal interface with surface plasmons is reported. When a white light is incident at a metal/liquid crystal interface, those photons in surface plasmon resonance frequency range are totally absorbed and the reflected light shows the complementary color. If a voltage is used to change the refraction index of the liquid crystal, then the surface plasmon resonance frequency will change, and the reflected light will also show the color change. The reflectance spectrum is calculated from a well‐known solution to the boundary value problem in optics. Good agreement with the observations is obtained. This phenomenon could lead to a new generation of display devices. ©1995 American Institute of Physics. 

ISSN:0003-6951    

DOI:10.1063/1.114584

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

A tapered‐stripe, traveling‐wave semiconductor optical amplifier was seeded with 3.3 mW of gain‐switched diode laser light to obtain over 200 mW average power with pulse widths≊105 ps full width at half‐maximum (FWHM) and a pulse repetition rate of 499 MHz corresponding to a peak power of 3.8 W. Shorter pulse widths were obtained when the amplifier was driven with less current at the expense of reduced output power. Pulse widths as short as 31 ps FWHM and an average power of 98 mW corresponding to a peak power of 6.3 W were obtained when a different, lower power seed laser was used. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114585

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The electro‐optic properties of polymer films are measured by an original technique whereby a periodic sequence of poling and probing steps permits alternation of the application of orientation and dephasing potentials. Relaxation dynamics of the electro‐optic coefficient of Red–Acid–Magly crosslinkable polymer films is studied as a function of the temperature of the samples. The time constant of the decay &tgr; as measured at several temperatures is found to follow a Vogel–Fulcher–Tamann—Hesse dependence, for temperatures above glass transition. Poling the samples in the presence of a pulsed electric field leads to ar33electro‐optic coefficient as high as 6 pm/V. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114586

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The results of modeling the application of an external electric field to disordered, strained InGaAs/GaAs single quantum well are presented. An error function profile is used to model the constituent atoms composition after interdiffusion. Results indicate that the exciton Stark shift in the disordered quantum well is greater than in the as‐grown 10 nm wide In0.2Ga0.8As well, and that the change in electroabsorption near the fundamental exciton absorption peak is enhanced by 30% in the disordered quantum well for a 30 kV/cm electric field applied perpendicular to the well. These results may be used to achieve optical modulators with improved performance characteristics in strained quantum well structures. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114587

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Variation of the reflectance of the aluminized tip of a near‐field scanning optical microscope is used to measure the temperature rise due the confinement of light in the tip. The measurement technique involves a pump‐probe beam approach, and uses a two‐step process which eliminates the need to know the dependence of the signal on the scattering cross section of the tip. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114588

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The effects of finite temporal duration on the spatial solitons in a planar optical waveguide are analyzed. The results show that (i) the self‐trapped pulses with finite temporal duration are unstable and collapse at higher peak power in a planar optical waveguide with the anomalous group velocity dispersion (GVD), but the collapse does not occur in a planar optical waveguide with the normal GVD; (ii) the spatial soliton with finite temporal duration has a transverse velocity which is proportional to the spatial width and inversely proportional to the temporal duration of the soliton, and the bright spatiotemporal solitons do not form multiple soliton bound states; and (iii) the peak power required for self‐trapping of the pulse in a planar optical waveguide with the normal GVD is less than the critical peak power for collapse of the pulses in a planar optical waveguide with the anomalous GVD. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114589

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

We report in this work a record low threshold (∼4 mA, cw), 1.55 &mgr;m wavelength, grating‐coupled surface‐emitting laser (GCSEL) which rivals all other existing SELs in the 1.3 or/and 1.55 &mgr;m regions. Methods to improve the asymmetric far‐field patterns and to obtain even lower threshold SELs are also demonstrated and/or suggested. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114590

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

We have experimentally obtained and theoretically analyzed a systematic map of the various instabilities induced in a semiconductor laser subject to strong optical injection as the amount of optical injection power and frequency detuning is varied. Two distinct islands of chaos have been identified in the injection‐locked region. They are separated by regions of period one and period two solutions. Spontaneous emission noise obscures the observation of high periodic orbits. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.114591

出版商:AIP    

年代:1995

数据来源: AIP