title: Laser shock wave-induced visible mechanoluminescence from semi-transparent organic crystals.
abstract: Indirect focusing of the output from a pulsed infrared Nd3+:YAG laser through a shock-generating layer onto organic crystals results in the emission of an intense microsecond duration pulse of mechanoluminescence (ML). The ML appears after a threshold laser fluence has been reached and increases sharply above this threshold. This specifies that there is a corresponding amplitude of a laser-induced shock wave that is necessary to induce crystal fracturing. Thus, the intensity of ML can be controlled by varying the laser fluence. Piezoelectric charges produced on the surfaces of a fractured crystal create the foundation for luminescence. Initially, the ML intensity increases with the shock wave pressure and time due to the creation of more surfaces in the crystal; the ML intensity reaches a peak value and then decreases over time. Thus, laser shock wave-induced ML provides a new optical technique for the study of materials under high pressure. Expressions explored for the characteristics of laser shock wave-induced ML satisfactorily explain the experimental results. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: School of Studies in Physics and Astrophysics, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, India.
authors.forename: V D
authors.initials: VD
authors.lastname: Sonwane
authors.affiliation: School of Studies in Physics and Astrophysics, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, India.
authors.forename: Anubha S
authors.initials: AS
authors.lastname: Gour
authors.affiliation: Department of Applied Physics, Raipur Institute of Technology, Raipur, Chhattisgarh, India.
authors.forename: Piyush
authors.initials: P
authors.lastname: Jha
mesh_terms: D003460:Crystallization; D007834:Lasers; D049449:Luminescence; D009930:Organic Chemicals / Q000737:chemistry*
chemical_list: D009930:Organic Chemicals
keywords: Nd3+:YAG laser; laser fluence; mechanoluminescence; piezoelectric charges; semi-transparent organic crystals