Accession Number : AD0751319

Title :   Far Infrared Isolator.

Descriptive Note : Final rept. 15 May 71-15 May 72,

Corporate Author : CASE WESTERN RESERVE UNIV CLEVELAND OHIO DIV OF ELECTRICAL SCIENCES AND APPLIED PHYSICS

Personal Author(s) : Pao,Yoh-Han ; Boord,W. T.

Report Date : 31 JUL 1972

Pagination or Media Count : 46

Abstract : It has been determined that optical isolators for linearly polarized (laser) beams of moderate power may be constructed with n-type InSb as the active element. The effect used in the device is the difference between the large free electron Faraday effect and the somewhat smaller interband Faraday effect. Somewhat unexpectedly, the authors find that the magnitude of the Faraday effect varies greatly with crystal orientation and absorption coefficients differ with suppliers of the crystals. In a typical device, the InSb wafer is about 0.38 mm thick, is maintained at liquid nitrogen temperature, has a donor (Te) concentration of about 3 x 10 to the 17th power/cc and provides 45 degrees rotation in a field of about 3500 Gauss. The dissipated power is less than 20% of the incident and there is no danger of thermal runaway for power densities up to 500 watts/sqcm. The quality of the isolation depends primarily on the quality of the analyzers used. (Author)

Descriptors :   (*GAS LASERS, OPTICAL EQUIPMENT), (*INFRARED OPTICAL MATERIALS, SEMICONDUCTOR DEVICES), INFRARED LASERS, REFLECTORS, INDIUM ANTIMONIDES, MAGNETOOPTICS, MAGNETS, SEMICONDUCTORS

Subject Categories : Lasers and Masers
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE