Work

Oxygen vacancies in LiB 3 O 5 crystals and their role in nonlinear absorption

Year: 2022

Type: article

Abstract: LiB 3 O 5 (LBO) crystals are used to generate the second, third, and fourth harmonics of near-infrared solid-state lasers. At high power levels, the material’s performance is adversely affected by nonlinear absorption. We show that as-grown crystals contain oxygen and lithium vacancies. Transient absorption bands are formed when these intrinsic defects serve as traps for “free” electrons and holes created by x rays or by three- and four-photon absorption processes. Trapped electrons introduce a band near 300 nm and trapped holes produce bands in the 500-600 nm region. Electron paramagnetic resonance (EPR) is used to identify and characterize the electrons trapped at oxygen vacancies (the unpaired electron is localized on one neighboring boron). Self-trapped holes and lithium vacancies with the hole trapped on an adjacent oxygen are also observed with EPR. At room temperature, we predict that most of the unwanted defect-related ultraviolet absorption created by a short laser pulse will decay with a half-life of 29 µs.

Source: Optical Materials Express

DOI: 10.1364/ome.469756

Authors: B. C. Holloway, C. A. Lenyk, T. D. Gustafson, N. C. Giles, D. Perlov, L. E. Halliburton

Institutions: U.S. Air Force Institute of Technology, IPG Photonics (United States)

Language: English

Topic: Crystal Structures and Properties

Subfield: Electronic, Optical and Magnetic Materials

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,843

Funder: National Research Council