摘要:

A longitudinal electro‐optic memory effect is observed in ferroelectric single‐crystal SrxBa1−xNb2O6with tetragonal symmetry. The changeable birefringence depends on the remanent polarization of the crystal and can be switched by voltage pulses. These optical characteristics, which seem to be similar to the optical properties observed in ferroelectric Pb3MgNb2O9with a diffuse phase transition, can be utilized in light‐valve devices which operate in the longitudinal mode without a transverse electric field or strain bias.

ISSN:0003-6951    

DOI:10.1063/1.1654700

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A theoretical approach of Rayleigh wave guidance is presented by using a simple optical analogy. The propagating modes are determined versus the geometry of the nondispersive guidance structure by introducing a critical angle of reflection. Theoretical results are compared to the results of an experimental investigation onYZLiNbO3by using optical probing.

ISSN:0003-6951    

DOI:10.1063/1.1654701

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The present letter demonstrates that significant population inversion can be achieved in the flow structure behind a blast wave if appropriate choice of the initial parameters is made. Typical numerical results are given for a cylindrical blast from a line source in a CO2&sngbnd;N2&sngbnd;He medium. The predicted peak population inversion levels are an order of magnitude better when compared with those achieved in the more conventional gas‐dynamic expansion systems using supersonic nozzles.

ISSN:0003-6951    

DOI:10.1063/1.1654702

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Energy‐loss measurements have been made for 2.0‐MeV4He ions in 20 targets. The energy‐loss cross sections were determined by analysis of thick‐target backscattering yields. Eight of the targets have been previously measured and support the accuracy of the present measurement. Twelve new heavy‐metal targets are evaluated: Pb, Au, Pt, Ir, W, Ta, Hf, Gd, Te, Sb, Mo, and Ge. By using the Lindhard‐Winther formalism with Hartree‐Fock‐Slater atomic charge distributions, the stopping cross sections for these metals are predicted down to 1.4 MeV.

ISSN:0003-6951    

DOI:10.1063/1.1654703

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A singly resonant parametric oscillator based on proustite has been operated for the first time. The device was pumped by aQ‐switched neodymium (1.065 &mgr;m) laser in a noncollinear phase‐matching geometry. The output has been tuned over the wavelength range 1.22–8.5 &mgr;m. The idler power was typically ∼100 W in a bandwidth of ∼1 cm−1.

ISSN:0003-6951    

DOI:10.1063/1.1654704

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Two‐photon‐excited laser action inn‐type InSb atT= 15 °K has been observed to occur at a threshold pumping intensity of 0.1 MW/cm2. The peak output power is estimated to be in excess of 20 mW. In a magnetic field, peaks in the laser output power are observed when twice the incident photon energy equals a Landau transition energy.

ISSN:0003-6951    

DOI:10.1063/1.1654705

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

In the high‐resistivity layer of vapor‐phase epitaxial GaAs films grown under the condition of relatively low arsenic vapor pressure, various interesting properties were found, such as (i) a large PTCR (positive temperature coefficient of resistivity), (ii) large photoconductivity, and (iii) current‐controlled negative resistance. A possible explanation is presented.

ISSN:0003-6951    

DOI:10.1063/1.1654706

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

In order to extend to the infrared range some of the interferometric methods utilized in radioastronomy, the heterodyne detection of 10.6‐m blackbody incoherent radiation has been accomplished, and the correlation between detected signals has been studied.

ISSN:0003-6951    

DOI:10.1063/1.1654707

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A pulsed HF chemical laser utilizing the chain reaction between H2and F2has been operated with electric discharge initiation. A uniform transverse discharge is made possible through the use of spark preionization. For the mixture 1:1:10:0.06 (F2:H2:He:O2) at 120 Torr total pressure an output energy 1.01 times the electrical input has been achieved. The corresponding chemical efficiency was ∼1.0%. A tradeoff is observed between electrical efficiency and chemical efficiency with the maximum chemical efficiency of 2% being achieved at an electrical efficiency of 25%. Even higher electrical efficiencies are expected with further device optimization.

ISSN:0003-6951    

DOI:10.1063/1.1654708

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Heterodyne detection is used to measure frequency sweeps in helical TE laser output. The heterodyne signal is analyzed and a model based on pressure‐induced index‐of‐refraction changes is proposed.

ISSN:0003-6951    

DOI:10.1063/1.1654709

出版商:AIP    

年代:1973

数据来源: AIP