Engineering Commons^™

Electronically Enhanced Surface Diffusion During Ge Growth On Si(100), Ali Orguz Er, Hani E. Elsayed-Ali

Physics Faculty Publications

The effect of nanosecond pulsed laser excitation on surface diffusion during the growth of Ge on Si(100) at 250 °C was studied. In situ reflection high-energy electron diffraction was used to measure the surface diffusion coefficient while ex situ atomic force microscopy was used to probe the structure and morphology of the grown quantum dots. The results show that laser excitation of the substrate increases the surface diffusion during the growth of Ge on Si(100), changes the growth morphology, improves the crystalline structure of the grown quantum dots, and decreases their size distribution. A purely electronic mechanism of enhanced surface …

Nano-Patterned High-Responsivity Gaas Metal-Semiconductor-Metal Photodetector, Ayman Karar, Chee Leong Tan, Kamal Alameh, Yong Tak Lee

Research outputs 2011

In this paper, we use the finite difference time-domain (FDTD) method to optimize the light absorption of an ultrafast nano-grating plasmonic GaAs metal-semiconductor-metal photodetector (MSM-PD) employing double metal nano-gratings. The geometry of the MSM-PD is theoretically investigated, leading to improved light absorption near the design wavelength of GaAs due to plasmon-assisted electric and magnetic field concentration through a subwavelength aperture. Simulation results show up to 8- and 21-times light absorption enhancement for the single and double nano-grating structure, respectively, in comparison to conventional MSM-PDs. Experimentally, more than 4 times enhancement in photocurrent is demonstrated for a single top nano-grating MSM-PD …

Precise Control Of Highly Ordered Arrays Of Nested Semiconductor/Metal Nanotubes, Diefeng Gu, Helmut Baumgart, Kandabara Tapily, Pragya Shrestha, Gon Namkoong, Xianyu Ao, Frank Müller

Electrical & Computer Engineering Faculty Publications

Lithographically defined microporous templates in conjunction with the atomic layer deposition (ALD) technique enable remarkable control of complex novel nested nanotube structures. So far three-dimensional control of physical process parameters has not been fully realized with high precision resolution, and requires optimization in order to achieve a wider range of potential applications. Furthermore, the combination of composite insulating oxide layers alternating with semiconducting layers and metals can provide various types of novel applications and eventually provide unique and advanced levels of multifunctional nanoscale devices. Semiconducting TiO₂ nanotubes have potential applications in photovoltaic devices. The combination of nanostructured semiconducting materials …

Switching Energy-Delay Of All Spin Logic Devices, Srikant Srinivasan

Srikant Srinivasan

A recent proposal called all spin logic (ASL) proposes to store information in nanomagnets that communicate with spin currents in order to construct spin based digital circuits. We present a coupled magnetodynamics/spin-transport model for ASL devices that is based on established physics and is benchmarked against available experimental data. This model is used to show the linear dependence of switching energy and quadratic dependence of energy-delay of ASL devices on the number of Bohr magnetons comprising a nanomagnet. A scaling scheme that could lower the energy-delay of spin-torque switching while maintaining thermal stability is discussed.

Fpga Implementation Of Pipeline Digit-Slicing Multiplier-Less Radix 2 2 Dif Sdf Butterfly For Fast Fourier Transform Structure, Yazan Samir, Rozita Teymourzadeh, Masuri Othman, Shabiul Islam

Dr. Rozita Teymourzadeh, CEng.

Optimised Toolbox For The Design Of Rotary Reluctance Motors, Grace I, Rozita Teymourzadeh, Bright S, Aravind Cv

Dr. Rozita Teymourzadeh, CEng.