Journal of the Optical Society of America B

Mechanism of high-density power-gated hole burning in Eu^2+-doped sulfides

Zameer U. Hasan, Levent Biyikli

Published Feb 1, 2001• 3 citations

Abstract

The mechanism for highly efficient photoionization spectral hole burning in the 4f7–4f65d1 transition of Eu2+ in MgS host is investigated in detail. The time and power dependencies of the hole depth and its photoerasure are analyzed assuming that a resonant two-photon ionization process initiates the hole burning. The near-room-temperature cycling shifts the hole to low energies, demonstrating the relaxation of an unstable lattice resulting from the hole burning. The characteristics of hole burning change significantly in samples codoped with Ce and Eu. All of these studies support that the mechanism of hole burning is the electron transfer from the Eu2+ ion to the Eu3+ deep trap, both of which are located at the substitutional octahedral sites.

DOI: 10.1364/josab.18.000232

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