Spectroscopy of tetravalent chromium in different hosts in search for new, tunable, broad band lasers in the 1.2 um band

Author

Chiranjit Deka, University of Central FloridaFollow

Abstract

Spectroscopic studies are presented for cr⁴⁺ ions in different hosts. The crystals investigated in this work are divided into two categories. In the first category are included crystals containing chromium in the tetravalent state only. These are purely cr⁴⁺ doped crystals. The second category crystals are more complex, containing chromium in both tetravalent and trivalent states. Detailed investigations of the absorption and luminescence characteristics of cr⁴⁺ in cr⁴⁺:Y 2SiO5, which is a purely cr⁴⁺ doped crystal, allowed a better understanding to be achieved for the spectroscopic behavior of cr⁴⁺ in tetrahedral sites. Based upon these studies theoretical model has been developed for the near infrared fluorescence dynamics of the cr⁴⁺ ion. This model now explains many of the inconsistencies and uncertainties that existed in earlier work on cr⁴⁺ ion in the more complex crystals such as Cr:Mg₂SiO₄ and can serve as a standard model for future studies of cr⁴⁺ in other materials. Also, laser action in the near infrared was demonstrated for the first time in a purely cr⁴⁺ doped material, cr⁴⁺:Y₂SiO₅. This confirms the identification of cr⁴⁺ as the lasing center responsible for the near infrared laser action in cr⁴⁺ doped crystals. The effects of site symmetry and charge compensation on the spectroscopic behavior of cr⁴⁺ ions in tetrahedral sites have been taken into account in the present work. This has enabled a new systematic approach to be developed for the crystal field engineering of improved cr⁴⁺ laser materials.

Graduation Date

1992

Semester

Fall

Advisor

Bass, Michael

Degree

Doctor of Philosophy (Ph.D.)

College

College of Arts and Sciences

Department

Physics

Format

PDF

Pages

139 p.

Language

English

Rights

Written permission granted by copyright holder to the University of Central Florida Libraries to digitize and distribute for nonprofit, educational purposes.

Length of Campus-only Access

None

Access Status

Doctoral Dissertation (Open Access)

Identifier

DP0022808

Subjects

Arts and Sciences -- Dissertations, Academic; Dissertations, Academic -- Arts and Sciences

STARS Citation

Deka, Chiranjit, "Spectroscopy of tetravalent chromium in different hosts in search for new, tunable, broad band lasers in the 1.2 um band" (1992). Retrospective Theses and Dissertations. 4400.
https://stars.library.ucf.edu/rtd/4400

Accessibility Status

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