Accession Number : AD0683232

Title :   OPTICAL-MICROWAVE DOUBLE-RESONANCE STUDIES OF RUBY,

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) RADIO AND ELECTRICAL ENGINEERING DIV

Personal Author(s) : Szabo,A.

Report Date : 08 JUL 1968

Pagination or Media Count : 11

Abstract : Studies of the resonant interaction of radiation from a liquid-nitrogen-cooled ruby laser with a ruby crystal in the temperature range 4.2 -100K are described. The interaction was measured by observation of the change which occurs in the Cr(3+) ground state EPR absorption on laser irradiation. At low radiation intensities, the temperature dependence of this change is shown to be determined by the well-known thermal tuning behavior of the R lines. Precise measurement of the relative laser and ruby-sample absorption frequencies by this technique of double-resonance spectroscopy is described. Under optical saturation conditions, additional temperature-dependent pumping effects occur at low temperatures. In particular, as the ruby temperature is increased from 4.2 to 40K, the laser-induced change in EPR absorption is observed to undergo a large increase. This increase cannot be explained by a relative thermal shift of the laser and absorption frequencies which is known to be very small in this temperature range. The phenomena are attributed in part to the temperature-dependent homogeneous linewidth which determines the widths of the holes burnt into the inhomogeneous strain-broadened R lines. Calculations indicate that the related temperature-dependent thermalization process which redistributes exicited Cr(3+) among the 2E levels quantitatively accounts for most of the increase. (Author)

Descriptors :   (*RUBY, *LASERS), OPTICAL PUMPING, RESONANCE, INTERACTIONS, CRYOGENICS, CHROMIUM, CRYSTAL DEFECTS, CANADA

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE