Prism-waveguide Coupling System Research Articles

Thermo-optic Imbert-Fedorov effect in a prism-waveguide coupling system with silicon-on-insulator

In this paper, a prism-waveguide coupling system based on silicon-on-insulator (SOI) is revisited. We find that thermo-optic Imbert-Fedorov (TOIF) effect displays in this four-layer optical system which has not been proposed before. Furthermore, we discuss the TOIF shifts in prism/SiO2/Si/SiO2 and prism/Au/Si/SiO2 waveguides with different parameters and study the observed phenomena from physical point of view. It is shown that the maximum IF shift can achieve 140μm in a prism/Au/Si/SiO2 waveguide which is large enough to be directly measured by the calculation results. Accordingly, TOIF shift provides a temperature control method for the enhancement and modulation of IF shift.

Large positive and negative lateral shift in prism-waveguide system with left-handed material of weak absorption

We study the mechanism of large positive and negative lateral shift in a prism-waveguide coupling system where the guiding layer is composed of left-handed material with weak absorption. As the giant lateral shift is always dramatically decreased by the loss of guiding layer, we introduce lossy cladding layer and substrate to realize large lateral shift in the above system, theoretical expression of lateral shift is derived and simulation results illustrate the appearance of large lateral shift.

Magneto-optical Goos-Hänchen effect in a prism-waveguide coupling structure.

We report a theoretical study of the enhanced Goos-Hänchen (GH) effect in a prism-waveguide coupling system with a magneto-optic thin film of Ce doped Y(3)Fe(5)O(12) (CeYIG). By magnetizing the CeYIG thin film along different directions, a variation of the GH shift can be observed, which is named as the MOGH (magneto-optical Goos-Hänchen) effect. The applied magnetic field direction is found to cause MOGH effect for light with different polarizations. As example systems, enhanced GH shift and MOGH effect is observed in both prism/Air/CeYIG/SiO(2) and prism/Au/CeYIG/SiO(2) structures, by applying opposite magnetic field across the CeYIG layer in a transverse magneto-optical Kerr effect (TMOKE) configuration. The GH and MOGH effect as a function of layer thicknesses, material refractive indices and magneto-optical properties are systematically simulated and discussed. It is observed that the coupling layer and MO layer thickness plays an important role of controlling the MOGH effect in the prism/Au/CeYIG/SiO(2) plasmonic waveguide structure. The MOGH effect shows high sensitivity to applied magnetic field and index variations, making it promising for applications such as optical switches, modulators, and chemical or biomedical index sensors.

Enhancement of Goos–Hänchen effect in a prism-waveguide system with biaxially anisotropic metamaterial

We study the mechanism of large lateral shift effect in a prism-waveguide coupling system where the guiding layer is composed of biaxially anisotropic metamaterial (BAM). We make use of stationary-phase approach to calculate the GH shift with different thickness of coupling layer and guiding layer, permittivity of coupling layer and imaginary parts of permittivity of BAM. Simulation results show that by the change of the above parameters, GH shift can be modulated sensitively. The physical explanation is given about these phenomenons and the proposed prism-waveguide system with BAM can be designed to realize different functions, such as thickness measurement, refractive index testing and absorption detection.

Net lateral shift of reflected beam in prism-waveguide coupling system due to guided wave resonance

When guided wave resonance occurs on the prism-waveguide coupling system (PWCS), the reflected beam undergoes angular shift which contributes to lateral shift of the reflected beam, in addition to the Goos–Hänchen (GH) lateral shift. We investigate the net lateral shift of the reflected beam at the Rayleigh range where the beam waist does not broaden obviously. It is shown that the incident angle associated with the maximum net lateral shift deviates from the resonant angle and the maximum net lateral shift is larger than GH shift. And at the same time, the net lateral shift is more sensitive than GH shift to the changes of PWCS parameters. Numerical simulation shows that the theory agrees well with numerical results when the beam width is large enough.

Refractive index detection based on a prism–waveguide coupling system with double-negative material

We construct a refractive index detection structure based on a prism–waveguide coupling system with double negative (DNG) material guiding layer, where surface plasmon resonance (SPR) is generated and the refractive index of lossless as well as lossy sample can be detected by the location of the incident light at which lateral shift peak appears. Simulation results show that when sample is lossy, more than one lateral shift peaks appear at different incident angle when other parameters are fixed once the intrinsic and radiative dampings satisfy the sufficient condition of equation for a large lateral shift.

Giant lateral shift in a prism-waveguide coupling system with anisotropic metamaterial and its application in precision processing

We study the lateral shifts of reflected light beams in a prism-waveguide system with uniaxially anisotropic metamaterial, and four sufficient conditions for the appearance of large lateral shift are determined. Based on the high sensitivity of the proposed system, we explore the application of the proposed prism-waveguide system in precision processing, including a sample counter used in production line and a planeness detector used in detecting the roughness of dielectric surface.

Origin of large lateral shift in a prism⿿waveguide coupling system with metamaterial

We study the lateral shifts of reflected light beams in a prism⿿waveguide system with lossless or lossy metamaterial, four sufficient conditions for the appearance of large lateral shift is concluded when the metamaterial is lossless, and the influence of lossy metamaterial on the properties of lateral shift is also analyzed by simulation results.

Experimental Investigation of First Hyperpolarizability by a Prism Coupling Waveguide Method

The complex first hyperpolarizability of chromophore for electrooptic effect has been determined by a prism coupling waveguide method. By measuring the field-induced changes in the reflected intensity of the prism–waveguide coupling system at different guided wave resonance dips, the real and imaginary parts of the first hyperpolarizability of the chromophore are simultaneously obtained without using the Kramers–Kronig transformation.

Physical origin of large positive and negative lateral optical beam shifts in prism–waveguide coupling system

Large lateral beam shift in prism–waveguide coupling system is theoretically analyzed from the viewpoint of interference between multiple reflected beam constituents. It is shown that the reflected beam is a result of interference between two beams: the beam directly reflected from the prism and the total leaky beam coming from guided mode. The thickness of coupling layer determines the amplitude of the total leaky beam, and further determines the sign (positive or negative) of the reflected beam shift. Because of interference between two beams, intrinsic damping itself plays an important role in deciding the distortion of the reflected beam.

Tunable Goos–Hänchen shift in a prism–waveguide coupling system with a nematic liquid crystal slab

In this paper, the tunable positive and negative lateral shifts on reflection from a prism–waveguide coupling system with a nematic liquid crystal (NLC) slab are analysed. The large positive and negative Goos–Hänchen shifts are due to the formation of ultrahigh-order modes in the NLC slab. The sign and the magnitude of the lateral shift can be conveniently controlled by adjusting the rotation angle (i.e. the applied driving voltage) as well as by altering the angle of incidence. Numerical simulations confirm the theoretical analysis.

Large positive and negative lateral optical beam shift in prism-waveguide coupling system

In this paper, the lateral beam shift in a prism-waveguide coupling system at wavelengths ranging from visible to near infrared is theoretically examined. A simple theoretical formula is derived to analyze the behavior of the beam shift. We demonstrate that large positive and negative lateral optical beam shifts can be obtained when guided modes are excited. It is also found that the magnitude of the beam shift is closely related to the intrinsic and radiative damping. When the intrinsic damping is larger than the radiative damping, negative lateral beam shift occurs. Numerical calculations confirm the theoretical analysis and show that a beam shift of the order of millimeters is possible.