Optical signatures of photoinduced Zn vacancies in ZnO single crystal
- Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)
193-nm excimer laser interaction with ZnO single-crystal at 0.05–500 KW/cm{sup 2} intensities is investigated under ultra high vacuum conditions by time resolved photoluminescence (PL) spectroscopy. A dominant 3.18 eV PL emission band at 295 K is observed. This band shows unusually long 0.52 ± 0.01 μs lifetime, indicating a defect mediated emission mechanism. The demonstrated negative thermal quenching for this band confirms its free electron to acceptor type transition. The involved acceptor is attributed to zinc vacancy with ∼100 meV shallow acceptor state. This study finds that 193-nm interactions produce Zn vacancies in transient states at 0.05–50 KW/cm{sup 2} excitation intensities and in stable state at 500 KW/cm{sup 2} or above intensities. The transient zinc vacancy production at such low intensities further validates the Frenkel pair creation as mechanism for creating these defects in ZnO single-crystal.
- OSTI ID:
- 22271279
- Journal Information:
- Journal of Applied Physics, Vol. 115, Issue 1; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Enhanced room temperature ferromagnetism in electrodeposited Co-doped ZnO nanostructured thin films by controlling the oxygen vacancy defects
Studies on intrinsic defects related to Zn vacancy in ZnO nanoparticles