摘要:

Spectra are presented of the responsivity and noise equivalent power (NEP) of liquid‐helium‐cooled InSb detectors as a function of magnetic field in the range 20–110 cm−1. The measurements are all made using a Fourier transform spectrometer with thermal sources. The results show a discernable peak in the detector response at the conduction electron cyclotron resonance (CCR) frequency for magnetic fields as low as 3 kG. The magnitude of responsivity at the resonance peaks is roughly constant with magnetic field and is comparable to the low‐frequency hot‐electron bolometer response. The NEP at the peaks is found to be comparable to the best long wavelength results previously reported. For example, we measure NEP=4.5×10−13W/Hz1/2at 4.2 K, 6 kG, and 40 cm−1. The InSb CCR will provide a much improved detector for laboratory spectroscopy, as compared with hot electron bolometers, in the 20–100 cm−1range.

ISSN:0021-8979    

DOI:10.1063/1.335989

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Capillary flow of 0.3% aqueous solutions of poly(ethylene oxide), 4×106MW, generates a fluctuating electrical signal (noise) between electrodes at the ends of the capillary. The frequency spectra of the noise are approximately of the 1/f &agr;type. Within certain flow rate ranges, two sets of harmonic peaks appear in the spectra. It is shown that these peaks are associated with the transverse and longitudinal modes of motion of the elastic solution entering the capillary. This equivalence has been verified by frequency analysis of the intensity of a laser beam transmitted through the entry region, and by high‐speed photography. The noise is assumed to reflect fluctuations in the streaming potential, caused by fluctuations in flow rate.

ISSN:0021-8979    

DOI:10.1063/1.335990

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

It is shown that for any finite‐energy solution of the free‐space Maxwell equations without sources, the energy contained in an infinite slab of finite thickness approaches zero as time tends to infinity.

ISSN:0021-8979    

DOI:10.1063/1.335964

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

In this work we report electroreflectance, photoreflectance, and photoabsorption measurements on CdTe polycrystalline thin films. These thin films were prepared by the gradient recrystallization and growth technique. The measurements were performed around the fundamental energy gap of the semiconductor at room temperature. The energy gap of this polycrystalline material coincides with that corresponding to the single‐crystal material, and the phenomenological energy broadening parameter is larger than that corresponding to the single‐crystal semiconductor by a factor of three, approximately. The photoabsorption signal is obtained by studying the origin of a low‐energy peak which appears in the photoreflectance spectrum.

ISSN:0021-8979    

DOI:10.1063/1.335965

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The existence of a new red &agr;’‐HgI2phase that occurs in a narrow temperature range prior to melting has been established. This phase allows the growth of single crystals within its stability range, which after quenching retain their monocrystallinity and transform to &agr;‐HgI2. The method is used to prepare single crystals of any desired volume either pure or doped.

ISSN:0021-8979    

DOI:10.1063/1.335966

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The decrease of the formation rate of Ni2Si from Ni‐Cr alloys as opposed to its formation from pure Ni is analyzed in terms of a paper published by Carl Wagner in 1952. Some possible ternary diffusion effects are pointed out.

ISSN:0021-8979    

DOI:10.1063/1.335967

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

It is demonstrated that the measured value of the self‐bias voltage on electrodes with an insulating target plate in a radio‐frequency dry etching system is strongly influenced by the configuration of the electrode, and may have no straightforward relation with the actual self‐bias voltage between the target surface and ground. The mechanism allowing measurement of the self‐bias voltage is identified as plasma‐induced surface conduction on the insulating target plate assisted by high electric fields at the target plate edge.

ISSN:0021-8979    

DOI:10.1063/1.335968

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The conductance versus frequency technique [G(&ohgr;)] and deep level transient spectroscopy (DLTS) are both used to characterize Si‐SiO2interface states. However, no direct comparison between the two methods has yet been performed. We have performed a systematic study, with these two techniques of the same metal oxide semiconductor structures (Si‐SiO2onn‐ andp‐type materials) made with various technologies and we have compared the performances of each technique: energy range accessible, energy resolution, sensitivity. We have shown that the conductance technique provides a density of states larger than the one obtained by DLTS, that its sensitivity and energy range are smaller. Its energy resolution is also smaller as illustrated by the fact that localized levels are detected by DLTS which are not with the conductance technique.

ISSN:0021-8979    

DOI:10.1063/1.335969

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

A connection between the temperature behavior of the internal magnetic field and Mo¨ssbauer linewidth broadening for a system which exhibits superparamagnetism is proposed.

ISSN:0021-8979    

DOI:10.1063/1.335970

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Protection against the destructive effects of a thermonuclear explosion requires a substantial defense against the light energy, the shock wave, and the radioactive fallout. Each can produce casualties either directly or indirectly as the result of fires and the destruction of property. Obviously, light can be intercepted by dyes and smoke. The amount of such material required per square mile to permit no more than a first degree burn at ground zero from a 10 MT weapon exploding at an altitude of three miles is calculated. The interaction of the heated air with the shock wave and radioactive debris is explored. It is shown that a substantial degree of protection from them should ensue.

ISSN:0021-8979    

DOI:10.1063/1.335971

出版商:AIP    

年代:1985

数据来源: AIP