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Electrically controlled lateral shift by an electro-optic crystal prism is studied theoretically. The resonance point of excitation of guided-wave surface plasmon resonance (GWSPR) can be controlled by altering the refractive index of the prism. That is to say, the positions corresponding to the least reflectivity and the largest lateral shift could be conveniently modulated while the lithium niobate prism is operated in an external electric field. The maximal lateral shift is obtained at the excitation of GWSPR when the thickness of the silver film is optimized. The results of numerical simulations confirm theoretical calculation.

According to the technical requirements of the tempo-spatially mixed modulated polarization imaging interference spectrometer (TSMMPIIS), we designed and verified the maximum optical path difference (OPD) through two different schemes, and analyzed the influences of the field of view and calcite dispersion on the OPD. When the angles between the incident plane and the principal section of the Savart left plate were 0 ° , 45 ° and 90 ° , we simulated the variations of the OPDs changing with different parameters. We found that the variations were proportional to the thickness t and the incident angle i . In order to reduce the influences of the Savart polariscope dispersion and field of view on the OPD, the corrected models were established, and the correctness was validated by the experiment. This work would provide theoretical and practical guidance for the design and engineering of the TSMMPIIS.

Large tunable lateral shift from guided wave surface plasmon resonance (GWSPR) is theoretically predicted. The dip of reflectivity and magnitude of the lateral shift can be controlled by the thickness of silver layer. The position of minimum reflection and maximum Goos-Hanchen (GH) shift can be conveniently adjusted by guided layer. The largest GH shifts at the optimal thickness of silver film can be hundreds of wavelengths when GWSPR is excited. The numerical calculation results from the Gaussian beam are in accordance with theoretical results.

Optical microscopy techniques have recently been shown to have the capability to exceed the diffraction limit when a microsphere is used. The mechanism involved in super-resolution imaging is theoretically analysed in this paper. A microsphere is also known to generate a photonic nanojet with a waist smaller than the diffraction limit. This nanojet is used as near-field illumination, and interacts with the sample to give a passive spatial frequency shift for the sample, meaning that near-field evanescent waves containing high-frequency spatial information about the sample can be converted into far-field propagating waves. This method is simple and cost-effective, and offers a promising approach for achieving far-field super-resolution imaging. Our theoretical analysis of super-resolution imaging is verified based on numerical and experimental results.

In view of the peer reviewer's suggestion, we sincerely make a further discussion of the paper published in Appl. Opt. (52 (2013) 6309–6315) titled “Multiple frequency bands of square split resonant rings and metal wires metamaterial”. We choose square split resonant rings (different in size) stacking in the X and Y axes, the same arrangement as the previous paper coupling in the Z axis, to form a two-layer or a three-layer metamaterial unit. All of the two-layer and three-layer units exhibit multiple negative pasbands. A comparison on the resonant frequencies with coupling cells in different directions is accomplished.

This paper presents the layout of achromatic snapshot imaging polarimeter (SIP) using modified Savart plates (MSPs) and working under nature light. The hybrid (refractive–diffractive) lenses are used to achieve the achromatic point-spread function (PSF), and the design probe the four Stokes vectors of the object by using polarization analyzing optics comprising two MSPs, a half wave plate, and an analyzer. In comparison with the monochromatic or quasi-monochromatic SIP using MSPs reported previously, the most remarkable property of the proposed layouts is to have the capability of directly detecting the object with natural illumination. Also, the configuration is more easily manipulated and robust than achromatic conventional Savart polariscopes reported previously in probing the object with axial movement. The feasibility is verified by numerical simulation for natural light.

A modified Sagnac imaging spectropolarimeter is conceptually described. It consists of a spectral-polarimetric modulator, a modified Sagnac interferometer with large optical path difference, and a CCD camera. This design modulates the Stokes components of the input light into different wave numbers and obtains the modulated interferogram in snapshot mode, and the spectra of the Stokes components can be separated and demodulated from the interferogram. The performance of the system is demonstrated through a numerical simulation, and a novel method is proposed to detect the polarization parameters including the degree of polarization and polarization direction for eliminating the aliasing effects between linear Stokes parameters. Compared with the existing imaging spectrometers, the modified Sagnac imaging spectropolarimeter can acquire one-dimensional spatial information and its full linear spectropolarimetric information in one exposure, and some other spatial information can be obtained by push-broom mode.

This work presents simulations and experimental measurements of two negative refraction metamaterial samples at microwave frequencies. The two samples are composed of Four-Triangle Split Resonant Rings and Metal Wires (FTSRRs–MWs) with different cell sizes which are found to play an important role in the location of resonant frequency. The small cell sample is chosen to recover the effective index by utilizing the simulative permittivity and permeability, as well as the angle detection from the experimental data. The experimental data shows good agreement with the simulation result.

A type of photonic multiple quantum well (PMQWs) structure made of two different photonic crystals (PCs) with two kinds of single-negative materials is investigated. It is demonstrated by transfer matrix method that omnidirectional resonance modes are generated. The number of the resonance modes can be controlled by adjusting the periodic structure of the constituents. The resonance tunneling modes are weak dependence on incident angle and the scaling of the barrier photonic crystals. When the losses are taken into account, the effects of the losses coming from ENG media and MNG media on the resonance modes are striking difference.

One-dimensional (1D) photonic crystal coupled microcavity structure containing indefinite metamaterials was investigated. The Wannier-Stark ladder (WSL) can be obtained in both the Bragg ordinary and the well-known omnidirectional band gaps by modulating widths of the cavities. The time-resolved transmission of a short pulse showed the existence of two types of optical Bloch oscillation in such structures. The transmission and the period of the oscillation are found to decrease with the increasing gradient δ.

Experimental measurements are presented of the SSRR-MW (square split resonant ring and metal wire) and CSRR-MW (C split resonant ring and metal wire) samples at microwave frequencies. The geometrical shapes of the metamaterial samples are found to play an important role in determining the resonant frequency. Different cells are chosen to stack into a two-layer or a three-layer metamaterial unit to realize multiple negative passbands. The effective parameters of three one-layer models, a two-layer unit, and a three-layer unit are retrieved from the simulation data. The composed models exhibit two or more negative bands by overlapping the passbands of the original cells, and broaden the negative refraction. The recovered parameters show good agreement with theoretical analysis.

The reflectance and reflection phase properties of one dimensional photonic crystals with anisotropic left-handed materials is investigated by transfer matrix method. It is demonstrated that the width of zero- n band gap is influenced by the incident angle, polarization, the proportion of lattice and the ratio of thickness，which is different from the zero- n band gap with isotropic left hand materials. The value of reflection phase is affected by incident angle and polarization and not affected by the proportion of lattice and the ratio of thickness. These characteristic may be useful for making photonic crystal phase compensators and the dispersion compensators.

We investigate the resonance tunneling modes of photonic double quantum well made of two photonic crystals with two different single-negative materials. It is found that these resonance modes split pairs, due to a coupling between two photonic wells. It is observed that when two photonic quantum wells are far away from each other, resonance modes appear as a single peak. And the quality factors of the transmittance resonance peaks can be greatly improved by increasing the period number of the outer barrier. The effects of the losses coming from ENG and MNG materials on the resonance modes are also specifically explored.

In this paper, a concept of multiple-band is proposed to broaden the bandwidth of the negative index metamaterials. The multiple-band, which is realized by a new metamaterial sample composed of the double-E-ring, has more than two negative refraction bands at comparable frequencies. When the metamaterial produces a multiple-band, the bandwidth can be greatly enhanced, yielding an increased numbers of negative bands. The experimental measurements and computer simulations for the multiple-negative-passband metamaterial at microwave frequencies are presented. The effective permittivity and permeability of several resonant frequencies are retrieved from the simulation scattering data, and the experimental measurements show good agreement with the simulative results.

This work presents experimental measurements of two square split resonant ring and metal wire (SSRR-MW) samples with different cell sizes at microwave frequencies. The geometrical sizes of the metamaterial cells are found to play an important role in the resonant frequency. Cells with different geometrical sizes are chosen to stack into a two-layer or three-layer metamaterial unit to realize the multiple negative passbands. The effective parameters of three separate SSRR-MW models (a one-layer unit, a two-layer unit, and a three-layer unit) are retrieved from the simulation data. The composed models exhibit two or three negative bands by overlapping the passbands of original cells and broadening the overall bandwidth. The recovered parameters show good agreement with the theoretical analysis.