Peilin Lang

Transmittance spectrum of surface plasmon polariton based filter with asymmetric double-ring resonator and switch

The transmittance spectrum of a plasmonic filter has been numerically simulated by the two-dimension (2D) finite-difference time-domain method. The filter is composed of two Metal-Insulator-Metal waveguides and a resonator with two different rings. The results show that the rising edge of the asymmetric resonator is steeper than that of symmetric one at each pass band. By embedding the liquid crystal in the resonator, the filter can act as an electro-optical switch. These results show potential applications on nano-optical devices.

A band-pass plasmonic filter with dual-square ring resonator

In this paper, we show the simulation of a plasmonic band-pass filter which consists of two surface plasmon polaritons (SPPs) waveguides and a resonator in metal–insulator–metal (MIM) structure. The resonator is formed by two square rings and a patch between them. The patch is a tiny rectangle cavity in order to transfer the SPPs from one ring to the other. The finite element method (FEM) method is employed in simulation. The results show that the dual-ring resonator performs better than a single ring does. The 3 dB bandwidth near the peak wavelength λ = 1054 nm is merely 31.7 nm. The resonant wavelength can be shifted by changing the side length of the square ring. This narrow band-pass filter is easy to fabricate and has potential applications in future integrated optical circuits.

A novel optical pressure sensor based on surface plasmon polariton resonator

We propose a Metal–Insulator–Metal structure consists of two surface plasmon polaritons (SPPs) and an H-shaped resonator. The reflectance spectrum is numerically simulated by the two-dimensional finite-difference time-domain method. The results show that this structure can act as a pressure sensor. To our knowledge, this is the first proposal to utilize the SPP resonator to form a pressure sensor. The size of the SPP resonator can be as small as a few hundred nanometers. The nano-scale pressure sensor opens a wide field for potential applications in biological and biomedical engineering.

A Novel Optical Temperature Sensor Based on Surface Plasmon Polariton Resonator

In this letter, we present a novel optical temperature sensor based on a nanoscale surface plasmon polariton (SPP) resonator. A bimetal layer is applied in the structure to detect the changes in temperature. The resonance wavelength of the SPP resonator shifts with the deformation of the bimetal layer. The effect of temperature on the refractive index of the material is also discussed. The finite element method is employed to numerically calculate the reflectance spectra. To the best of our knowledge, it is the first design of an SPP temperature sensor based on thermal deformation, and this structure may be applied in the future integrated optical circuit.

Surface plasmon polariton based band-pass and stop-band filters in symmetric double ring resonators

We carried out the numerical simulations on plasmonic filters composed by a Metal–Insulator–Metal (MIM) waveguide and a resonator of double rings. Both the band-pass filter and stop-band filters are discussed. The results show that the characteristic wavelengths of the band-pass or stop-band filter have red shift when the size of the resonator increases. The filters of double-ring resonator show better sensitivity on the wavelength than the one for the single ring. The simulations are based on the two-dimensional (2D) finite-difference time-domain (FDTD) method. The introduced filters have potential applications on optical integrated circuits.

An optical pressure sensor based on π-shaped surface plasmon polariton resonator

We propose a metal–insulator–metal (MIM) structure which consists of a π-shaped resonator and a surface plasmon polariton (SPP) waveguide. The finite element method (FEM) is employed in the simulation. The results show that this structure forms an optical pressure sensor. The transmission spectra have a redshift with increasing pressure, and the relation between the wavelength shift and the pressure is linear. The nanoscale pressure sensor shows a high sensitivity and may have potential applications in biological and biomedical engineering.

The Transmission Characteristics of Surface Plasmon Polaritons in Double Rings Symmetric Structure Resonator

A nanoscale waveguide structure coupled with two rings is reported. We use 2D FDTD method to simulate the transmission characteristic of SPPs in this structure. Results show it can act as a SPPs band-pass filter.

Theoretical analysis and experiment performance of slow-light based on stimulated Brillouin scattering (SBS)

Slow light technology will play a key role in future all-optical communication. The slow-light technology based on stimulated Brillouin scattering has become a research highlight because of its additional advantages, such as compatibility of the devices with existing telecommunication systems, room-temperature operation, and tunable at arbitrary wavelengths. According to the propagation of a cw pulse through a Brillouin fiber amplifier, whose frequency is near the Stokes resonance, via three-wave coupling equations, both pump depletion and fiber losses taken into consideration, the principle of how slow-light effect based on stimulated Brillouin scattering produced and the mathematical expression of time delay are strictly deduced. A delay of 8 ns is obtained when the input Stokes pulse is 200ns and the SBS (stimulated Brillouin scattering) gain G is ~18 in our designed experiment of SBS slow-light system. Then the extent of transformation from pump waves to Stokes waves is measured using MATLAB numerical simulation according to the experiment dates, based on the relation between output pump light power and input pump light power and also the relation between output Stokes light power and input pump light power. And the relation between the input light power and propagation distance is discussed as well. Finally the relation between slow light pulse delay and SBS gain is also obtained.

Finite element analysis of the InP nano inner cladding fiber

We proposed that nanomaterials can be used to change the characteristics of standard fibers. After two stages, preform fabrication and fiber drawing, a novel inner cladding fiber with InP nano thin film has been successfully fabricated by the means of MCVD. The thickness of the InP film is about 60nm. The electric field distribution is simulated through the the finite element method. The simulation result indicates that the InP nano film can confine the electric distribution in the core. In addition, it is calculated that the effective refractive index is 1.585.

Flat suppercontinuum generation in the inner cladding fiber with InP nano thin film

We present the fabrication procedure of a novel inner cladding fiber with InP nano-thin film. A flat supercontinuum over 100nm in the telecommunication band is generated by infecting 1550nm, 120fs, 50MHZ repetition rate optical pulse into this kind of fiber. The supercontinuum generation of different fiber lengths and at different pump power is studied. The results indicate that the width of the supercontinuum spectra can be influenced by the fiber length and pump power. The longer fiber at higher pump power can produce broader supercontinuum spectrum.