Femtosecond UV laser non-ablative surface structuring of ZnO crystal: impact on exciton photoluminescence

Journal Article · Mon Mar 15 00:00:00 EDT 2010 · Journal of the Optical Society of America. Part B, Optical Physics

DOI:https://doi.org/10.1364/JOSAB.27.000531· OSTI ID:22053921

Museur, Luc ^[1]; Michel, Jean-Pierre ^[2]; Portes, Patrick; Kanaev, Andrei V ^[3]; Englezis, Apostolis; Stassinopoulos, Andreas; Anglos, Demetrios ^[4]

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1. Laboratoire de Physique des Lasers (LPL), UMR 7538 CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France)
2. Laboratoire des Proprietes Mecaniques et Thermodynamiques des Materiaux (LPMTM), UMR 9001 CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France)
3. Laboratoire d'Ingenierie des Materiaux et des Hautes Pressions (LIMHP), UMR 1311 CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France)
4. Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), 71110 Heraklion, Crete (Greece)

The ultraviolet (UV) laser irradiation (248 nm) of monocrystalline wurtzite ZnO with 450 fs pulses results in surface modification. A formation of two orthogonal ripple structures with a period of 400-500 nm was observed oriented parallel and perpendicular to the laser beam polarization. The UV exciton emission obtained on the irradiated domains is found greatly enhanced locally up to {approx}10{sup 3} times. The photoluminescence band is redshifted by 2-3 nm and 40% narrower (full width at half-maximum), while at the same time the E{sub 2} (439 cm{sup -1}) Raman band intensity increases up to {approx}50 times. The process is found irreversible with the threshold fluence of 11 mJ/cm{sup 2}, which is considerably lower than the ablation threshold 115 mJ/cm{sup 2}. Fine surface nanostructuring on the scale of {approx}10 nm may be responsible for the observed effect. (c) 2008 Optical Society of America.

• OSTI ID: 22053921
• Journal Information: Journal of the Optical Society of America. Part B, Optical Physics, Vol. 27, Issue 3; Other Information: (c) 2010 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA); ISSN 0740-3224
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CRYSTALS
EMISSION SPECTRA
EXCITONS
LASER MATERIALS
LASER RADIATION
PHOTOLUMINESCENCE
POLARIZATION
RAMAN SPECTRA
SEMICONDUCTOR LASERS
SEMICONDUCTOR MATERIALS
SURFACES
ULTRAVIOLET RADIATION
VISIBLE RADIATION
ZINC OXIDES