CC BY
17PH-I-9
Laser optoacoustics of micro- and nanostructures
O. Romanov1'2
1Belarusian State University, Department of Computer Simulations / Faculty of Physics, Minsk, Belarus
2HiLASE Centre, Institute of Physics of the Czech Academy of Sciences, Dolni Bfezany, Czech Republic
The photoacoustic (optoacoustic) effect is the formation of sound waves due to absorption of the modulated light pulse by irradiated medium. At the present time, the photoacoustic effect is widely used in biomedical studies (optoacoustic tomography), photoacoustic spectroscopy etc. Of particular interest are studies of the interaction of pulsed laser radiation with absorbing micro- and nanostructures. Absorption of pulse energy of the laser beam in materials with variation of the linear dimensions of the absorbent structures ranging from micro- to nanometers allows exciting acoustic oscillations in the frequency range from gigahertz to terahertz. Terahertz frequency acoustic vibrations are of special interest for fundamental research and have numerous potential applications (acoustic imaging of nano-objects, acoustic nanocavities, phononic crystals).
In this work a technique of the numerical simulation of equations of motion of continuous media in the form of Lagrange for a spatially inhomogeneous media (one, two, and three-dimensional micro- and nanostructures) has been developed. This model allows calculating fields of temperature, pressure, density and velocity of the medium depending on the parameters of laser pulses and the characteristics micro- and nanostructures. Examples of implementation of the model are discussed in connection with possible applications in the area of nanophotonics, nanoacoustics, and nanoplasmonics [1-3].
References
[1] N. Khokhlov, G. Knyazev, B. Glavin, Y. Shtykov, O. Romanov, V. Belotelov. Interaction of surface plasmon polaritons and acoustic waves inside an acoustic cavity. // Optics Letters, Vol. 42, Issue 18, pp. 3558-3561 (2017).
[2] Y.K. Shtykov, O.G. Romanov. Modeling of thermomechanical action of femtosecond laser pulses on metallic nanogratings // Nonlinear Phenomena in Complex Systems, 2018, Vol.21, No.2, pp.164 -171.
[3] V.I. Belotelov, A.N. Kalish, G.A. Knyazev, E.T.T. Nguen, O.G. Romanov, A.L. Tolstik. Optoacoustical transducer based on plasmonic nanoparticles // Nonlinear Phenomena in Complex Systems, 2019, V.22, N1, P.55-63.
