Accession Number : ADA331656

Title :   Material Engineering Novel Semiconductor Structures

Descriptive Note : Final rept. 16 Mar 94-15 Mar 97

Corporate Author : JOHNS HOPKINS UNIV BALTIMORE MD HOMEWOOD RESEARCH ADMINISTRATION

Personal Author(s) : Khurgin, Jacob B.

PDF Url : ADA331656

Report Date : MAR 1997

Pagination or Media Count : 14

Abstract : This research has focused on using the methods of 'band-gap engineering' to improve various electronic and optical properties of materials. From an experimental point of view, it has achieved the capability of routinely performing photoluminescence, photoconductivity and photoluminescence excitation measurement at the JHU faciltites. Among the most important theoretical results are advances in intersubband lasers and raman oscillators, especially a new "inverted effective mass" scheme. A theory of optical generation of THz radiation in bulk semiconductors and QW's has been developed to explain the experimental results of other groups. A major achievement has been the development of a rigorous theory for a group of phenomena commonly known as 'lasing without inversion'. For the first time we have developed expressions for threshold and slope efficiency and have come to conclusion that at least for our case of interest-quantum-confined semiconductor structures 'lasing without inversion' does not offer any advantage over more conventional schemes.

Descriptors :   *STRUCTURES, *SEMICONDUCTORS, OSCILLATORS, ELECTRONICS, OPTICAL PROPERTIES, ELECTROOPTICS, COMPOSITE MATERIALS, EXCITATION, ELECTROMAGNETIC PROPERTIES, QUANTUM WELLS, PHOTOLUMINESCENCE, EFFICIENCY, OPTICAL MATERIALS, LASERS, SLOPE, INVERSION, ENERGY BANDS, RAMAN SPECTRA, PHOTOCONDUCTIVITY, BULK SEMICONDUCTORS.

Subject Categories : Lasers and Masers
      Electrooptical and Optoelectronic Devices
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE