Abstract
Experimental and numerical results about the propagation of optical signals in a bidirectional two-wave mixing system with Au nanocomposites and carbon nanotubes are presented. Au nanoparticles embedded in a TiO2 thin solid film were prepared by a sol-gel processing route; while carbon nanotubes were obtained by a thermal decomposition approach. A thin film conformed by carbon nanotubes was put on top of the Au nanocomposites for the nonlinear optical measurements. A two-wave mixing experiment was conducted to distinguish the direction of propagation of a probe-beam through the exploration of an induced birefringence and two-photon absorption. The third-order nonlinear optical response of the sample was evaluated by considering discrete groups of energy numerically modeled by the beam propagation method. Remarkable differences exhibited by the propagation and counter-propagation of a polarized probe beam were identified by nanosecond pulses at 532 nm wavelength. By employing a 405 nm wavelength as a probe beam, we were able to change the behavior of the direction of maximum Kerr transmittance in a particular geometry of a non-degenerated multi-wave system. It can be contemplated that the influence of distinctive near- and off-resonant excitations of the samples seems to be useful to control a selective one-way transmittance with potential applications for developing all-optical systems.
Original language | English |
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Article number | 085804 |
Journal | Physica Scripta |
Volume | 90 |
Issue number | 8 |
DOIs | |
State | Published - 1 Aug 2015 |
Keywords
- Kerr effect
- nanosystems
- nonlinear optics