摘要:

An electric‐field‐induced cholesteric‐nematic transition on a sample containing a europium chelate guest molecule of little or no polarization shows contrast ratios as high as 9 : 1 for its brilliant red (612 nm) fluorescence.

ISSN:0003-6951    

DOI:10.1063/1.89528

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A dose dependence in the effectiveness of a two‐step annealing procedure for As‐implanted ⟨111⟩ silicon has been observed. The upper limiting dose for which two‐step annealing is more effective than a single‐step 900 °C anneal is ∼2×1015As/cm2. Increasing the annealing temperature above 900 °C reduces the dose for which two‐step annealing is more effective than single‐step annealing.

ISSN:0003-6951    

DOI:10.1063/1.89529

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Z‐cut lithium niobate has been subjected to shock loading over a wide stress range to determine the general character of its response. Unusual electrical and mechanical effects are observed.

ISSN:0003-6951    

DOI:10.1063/1.89530

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

High‐voltage high‐current pulses of electrical energy (700 V, 14 A, 10 kW) are generated with efficiencies greater than 0.1% for a duration of 30 nsec when a 3–4‐J CO2TEA laser is focused on a copper cathode in a special vacuum cell designed to collect the ejected high‐energy electrons. Potential applications as a high‐voltage source and as a detector are discussed.

ISSN:0003-6951    

DOI:10.1063/1.89531

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A new device for the absolute calibration of cells for photoacoustic spectroscopy is described. Experimental results for a particular cell are reported.

ISSN:0003-6951    

DOI:10.1063/1.89532

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

The performance of the 14‐ and 16‐&mgr;m CO2lasers produced in the electric discharge gasdynamic laser has been significantly improved by the addition of a small percentage of H2to deactivate the (0110) level. This addition tripled the pulsed output of the laser, and 45 &mgr;J at 14 &mgr;m and 25 &mgr;J at 16 &mgr;m were observed. cw oscillation was achieved for the first time, with output powers of 0.6 and 0.9 W, respectively. The effect of collisional processes in limiting the CO2density is discussed.

ISSN:0003-6951    

DOI:10.1063/1.89533

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A neodymium‐phosphate glass oscillator mode locked using the saturable absorber dye No. 3955 in a plastic host has been shown to give completely modulated outputs. Single pulses of duration ∼5 psec with the low background have been obtained, when operating close to threshold. The aperature time of the dye in the plastic host was measured to be 130±25 psec.

ISSN:0003-6951    

DOI:10.1063/1.89534

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Investigation of TE discharges in a 1.6‐mm square channel has revealed reasons for the inefficient operation of such devices as CO2oscillators. At high repetition rates the pulsed glow discharges are not wall confined above 100 Torr. Thus wall cooling and complete volumetric excitation are reduced. Energy deposited into the cathode fall region creates considerable problems. At low pressures this energy is a large fraction of the total discharge energy, whereas for higher pressures the power and power density deposited in this region is very high. The resultant localized gas heating dissociates molecules, creates turbulence, and limits gain.

ISSN:0003-6951    

DOI:10.1063/1.89535

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

The role of the electric field to pressure ratio (E/p) in waveguide CO2TE lasers is shown to be different from that in conventional CO2TE lasers. For waveguide CO2TE lasers, the optimumE/pin the positive column is greater than that which produces the most efficient excitation of CO2vibrational levels, because of the necessity to reduce the detrimental effects of the power dissipated in the cathode fall region of the discharge. Experimental results on small‐signal gain versus input energy as a function ofE/pare shown to be in agreement with theory. Implications for device design are discussed.

ISSN:0003-6951    

DOI:10.1063/1.89521

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Efficient combining of optical power from three input optical fibers to a single trunk fiber is demonstrated using fibers of different core/cladding diameters in a biconical taper configuration. The combiners have insertion loss less than 1 dB and optical isolation greater than −50 dB.

ISSN:0003-6951    

DOI:10.1063/1.89522

出版商:AIP    

年代:1977

数据来源: AIP