We demonstrate the fabrication of two-dimensional (2D) metallic photonic crystals (MPCs) based on colloidal gold
nanoparticles, where laser interference ablation combining subsequent high temperature annealing is employed for the
construction of 2D gold nano-dot arrays in square lattices. The microscopic and spectroscopic properties of the 2-D
MPCs are systematically characterized by the scanning electron microscope and the angle-resolved optical extinction
spectroscopic measurements, the strong coupling between the waveguide resonance mode and the particle plasmon
resonance of the MPCs imply the success of the fabrication method, which show potential applications in optoelectronic
devices and sensors.
In this paper a novel acousto-electro-optic (AEO) modulator that combined acousto-optic effects and electro-optic effects
is presented. Based on the design of Acousto-optic modulator (AOD), electro-optic effects is also utilized by sticking
Direct current (DC) electrodes to AOD surface, which direction of the electric field is perpendicular to the acoustic plane
and the incident light. The operating mode of the AEO device is systimatically studied for the first time and the optimum
operating mode is determined; we designed and made a modulator of centre frequency 60 MHz using LiNbO3 crystal,
which can realize acousto-optic effects and electro-optic effects at the same time. The experiments results show that this
novel modulator can not only realize light modulation, but also has a wider 3db bandwidth, which is agreed with the
theoretical analysis. This novel modulator has wider applications in optic communication and optic signal processing.
In this paper the beam steering theory in isotropic acousto-optic (AO) device is studied. In the process to design an AO deflector, it is important that the device has wider 3db Bragg bandwidth and uniform diffraction efficiency in frequency band. According to the theory about isotropic AO interaction, we can obtain wider 3db bandwidth by using technology of ultrasonic beam steering. It means, the momentum match condition can be satisfied at two track frequencies. The author gains the optimum track frequencies for various numbers of transducer pieces in plane and step configurations respectively. Based upon this argument, farther on, the optimum design parameter of the isotropic AO deflector is also shown up.
In this paper we researched principles of three-dimensional (3-D) isotropic acousto-electro-optic (AEO) modulator, including coupled wave equations and diffraction efficiency formula of the 3-D AEO effect. The AEO crystal is worn into a column of six side-faces. Three transducers are stuck on adjacent side-faces and they can produce three acoustic energy channels of 60° each other in acoustic plane. Direct current (DC) electrodes with central holes are plated on the end-faces. Through the hole, incident light propagates along axis of the column, which is perpendicular to the acoustic plane. So the acousto-optic (AO) effect must be Raman-Nath effect, it can realize 3-D light deflection. The DC electric field is supplied along the axis of the column too. So the electro-optic (EO) effect must be longitudinal, it can realize light modulation. We designed and made a 3-D isotropic AEO modulator of centre frequency 50 MHz using Potassium Hydrogen Phosphate (KDP) crystal, and measured its modulation curve of relative diffraction efficiency vs DC voltages. Measured results agree with theoretical calculation. Multi-dimensional AEO modulator has applications in multi-channel optic communication and optic signal processing.