Modelling Various Solar Cells Materials Using Lorentzian-Drude Coefficients

In order to develop an optoelectronic model for simulating different light trapping structures sandwiching the photovoltaic active layer, determining the materials dispersion and absorption properties is a must. The targeted model should be able to simulate the desperation and absorption capabilities of different conductor and semiconductor materials over the entire sun spectrum (200 nm to 1700 nm). Therefore, the Lorentzian-Dude (LD) model is chosen due to its simplicity in implementation with the finite difference time domain algorithm chosen for optical modelling. In this paper, various materials are selected to be modelled with the LD model. The proposed algorithm is not only used for modelling material behaviour of various conducting materials published in literature, but is also used for other conducting and semiconducting materials that the original model was not capable of modelling over the entire range of spectrum. Besides that, the suggested algorithm showed a better time performance than those mentioned in literature. Experimental 1D grating structure prototype samples were made to validate the simulation results, showing perfect agreement.

Photonic active filters based on SiC multilayer structures

ABSTRACTTunable WDM converters based on amorphous SiC multilayer photonic active filters are analyzed. The manipulation of the magnitude is achieved through appropriated front and back backgrounds. Transfer function characteristics are studied. Results show that the light-activated device combines the demultiplexing operation with the simultaneous photodetection and self amplification of an optical signal. Depending on the wavelength of the external background and irradiation side, it acts either as a short- or a long- pass band filter or as a band-stop filter. A combinational logic function is mapped onto an active two stage optoelectronic logic circuit. An algorithm to decode the multiplex signal is established. An optoelectronic model supports the optoelectronic logic architecture.

Optical bias controlled amplification in tandem Si-C pinpin devices

ABSTRACTA monolithic double pi’n/pin a-SiC:H device that combines the demultiplexing operation with the simultaneous photodetection and self amplification of the signal is analyzed under different electrical and optical bias conditions at low and high excitation frequencies. Results show that the transducer is a bias wavelength current-controlled device that make use of changes in the wavelength of the background to control the power delivered to the load. Self optical bias amplification or quenching under uniform irradiation and transient conditions is achieved. The device acts as an optical amplifier whose gain depends on the background wavelength and frequency. An optoelectronic model supported by an electrical simulation explains the operation of the optical system.