摘要:

A direct measurement of atomic flux ine-beam evaporated yttrium has been demonstrated with a diode-laser-based atomic absorption (AA) monitor at 668 nm. Atomic number density and velocity were measured through absorption and Doppler shift measurements to provide the atomic flux. The AA-based deposition rates were compared with independent quartz crystal monitors showing agreement between the two methods. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119460

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We have developed modified poly(p-phenylene vinylene) (PPV) to improve its performance in organic electroluminescent devices. Encapsulated single-layer devices with this PPV on indium–tin oxide and a calcium cathode have been operated in air for>7000 hat 20 °C and>1100 hat 80 °C without noticeable degradation. Devices fabricated with this PPV, a conducting polymer layer as anode, and a sputtered low work-function alloy as cathode have efficiencies of over 2 lm/W, brightnesses of>600 Cd/m2at 4 V, and lifetimes of>1400 hdriven at∼100 Cd/m2initial brightness. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119483

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

A system that makes it possible to precisely and instantaneously observe a potential energy of laser trapping as a function of three-dimensional position was developed for analyzing radiation pressure acting on a single microparticle in solution. Position sensing with a quadrant photodiode and total internal reflection microscopy are applied for measuring thermal Brownian motion of the trapped particle with∼10 nmresolution, and a trapping potential profile is estimated by a thermodynamical analysis based on the Boltzmann distribution. Characteristic features of the present system are discussed. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119461

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Experimental demonstration of lasing in a broad area twin-contact semiconductor laser which operates as a phase-conjugation (PC) mirror in an external cavity configuration is reported. This allows “self-aligned” and self-pumped spatially nondegenerate four-wave mixing to be achieved without the need for external optical signals. The external cavity laser system is very insensitive to tilt misalignments of the external mirror in the PC regime and exhibits very good mechanical stability. The resonant frequency of the external cavity lies in the GHz range which corresponds to a subnanosecond time response of phase conjugation processes in the semiconductor laser. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119462

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Photostimulated luminescence phenomena have been observed inCe3+-doped alkali borate glasses prepared under a reducing atmosphere. When the x-ray irradiated glasses were excited by a He–Ne laser (633 nm), photostimulated luminescence at about 360 nm due to the5d–4ftransition ofCe3+ions was observed. The intensity of photostimulated luminescence of theCe3+-doped alkali borate glasses increased in the order of lithiumborate<sodium borate<potassium borate.The luminescence appears to result from the photostimulated recombination of hole and electron traps which leave electrons in a long-lived excited state. ©1997 American Institute of Physics. 

ISSN:0003-6951    

DOI:10.1063/1.119463

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We report observation of reverse saturable absorption inC60toluene solution for 10 ns duration laser pulses in the wavelength region 710–740 nm, for which the photon energy is less than the energy of the lowest excited singlet state. The observed nonlinear absorption appears to be due to excitation of molecules to the more absorbing lowest triplet state by direct absorption from the ground state. Our results imply that aC60based optical limiter can operate over a broad spectral range extending into the near-infrared. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119464

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

To interpret the observed anomalous properties of weakly ionized gas-discharge plasma, the modified van der Waals’ equation of state for real gases was used. Use of this equation provides a possible explanation for the anomalous phenomena. The analysis allows the deduction that, in addition to the kinetic energy, there exists in the plasma a reservoir of potential energy from particle interaction. Estimates indicate the feasibility and potential expediency of applying this feature of gas-discharge plasma to practical problems in gas dynamics. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119484

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Perfluoropolyether (PFPE) films for lubrication of thin film magnetic recording media are made progressively thinner and their physical properties are increasingly dominated by molecular interactions with the carbon overcoat. Surface potential measurement is one of a few techniques to study the interaction of ultrathin films with surfaces. A scanning Kelvin probe apparatus with spatial resolution of 100 microns and potential sensitivity of 0.5 mV was employed to study the surface potentials of linear and branched PFPE films with methyl, hydroxyl, phenyl ester, and carboxylic acid end groups on amorphous hydrogenated carbon surfaces. The surface potential is dominated by polar groups rather than the PFPE monomers. Application of the scanning surface potential technique to measure the migration of PFPE films is also shown. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119466

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Results from a spectromicroscopic study of the formation ofTiSi2in patterned structures are reported. An x-ray spectromicroscope was used to acquire spectra and images with photoabsorption signals using synchrotron radiation. A patternedTiSi2sample with feature sizes ranging from 100 &mgr;m to 0.1 &mgr;m was studied. The silicidation reactions were carried out in ultrahigh vacuum using rapid thermal processing. Lateral variations in the local chemistry of the titanium silicide could be directly imaged and are attributed to the formation of the C54 phase in large areas and the C49 phase at feature edges and in narrow features. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119467

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

The effects of carbon addition on thermal stability and hardness ofZr41Ti14Cu12.5Ni10Be22.5bulk amorphous alloy were investigated. It is found that a small amount of carbon addition further extends the supercooled liquid range and enhances the thermal stability and strength of the alloy. More carbon addition results in the formation of a crystalline and amorphous mixture accompanied by a pronounced increase in microhardness. The effects of the carbon addition on the amorphous alloy are discussed from the structural point of view. ©1997 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.119468

出版商:AIP    

年代:1997

数据来源: AIP