Many high-efficiency photovoltaics concepts require an advanced control and manipulation of the optoelectronic properties of the active device structure, leading to a prominent role of low dimensional absorbers such as quantum wells, wires and dots in the implementation of these concepts. However, the quantum effects governing the optoelectronic characteristics of the nanostructures not only provide the desired design degrees of freedom, but also request new models for the description of the …

This is a video taped live lecture covering roughly the same material as lecture 1 of \“Concepts of Quantum Transport\”. Video only.

Quantum computers would represent an exponential increase in computing power…if they can be built. This tutorial describes the theoretical background to quantum computing, its potential for several specific applications, and the demanding challenges facing practical implementation. The field currently suffers from a strange imbalance with theoretical advances far outstripping experimental demonstration. The field is poised for a breakthrough that would make quantum circuits experimentally \“accessible\”, as opposed to the million dollar price tags attached to most current implementations.

First, I will discuss the physics and applications of 2D heterostructures composed of stacked monolayers of MoSe_2 and WSe_2 . These heterostructures host interlayer valley excitons where the electrons and holes are located in different layers. These spatially indirect excitons exhibit long lifetimes and valley polarization times which are promising for valley based information applications and for investigating long-range spin transport phenomena. Second, I will discuss single excitons localized to defects in monolayer WSe_2 , which are shown to be single photon emitters. I will discuss the physics of these localized quantum states as well as their potential quantum photonics applications....

The goal of this series of lectures is to explain the critical concepts in the understanding of the state-of-the-art modeling of nanoelectronic devices such as resonant tunneling diodes, quantum wells, quantum dots, nanowires, and ultra-scaled transistors. Three fundamental concepts critical to the understanding of nanoelectronic devices will be explored: 1) open systems vs. closed systems, 2) non-equilibrium systems vs. close-to-equilibrium systems, and 3) atomistic material representation …

Simulate the device-level characteristics of spin-based quantum gates.

Computes the electronic and phonon structure of various materials in the spatial configuration of bulk , quantum wells, and wires

By completing the Quantum Dot Lab, users will be able to a) understand the 3D confinement of carriers in a quantum dot, b) describe effects of geometry of a quantum dot on the energy states of carriers, and c) study light absorption of a quantum dot.

The specific objectives of the Quantum Dot…

Full-band 3D quantum transport simulation in nanowire structure

Compute the eigenstates of a particle in a box of various shapes including domes and pyramids.

Metamaterials—artificially structured microcircuits that can mimic the electromagnetic response of atoms and molecules—have vastly expanded the opportunities available for the design of electromagnetic structures. Starting in 2000 with the first report of a “left-handed” metamaterial, for which both the electric permittivity and magnetic permeability are simultaneously less than zero, metamaterials have been demonstrated to exhibit properties either difficult to achieve or non-existent …

Frequency domain simulation of single-period multilayer gratings and optical metamaterials upon TE/TM plane-wave incidence at arbitrary angles

Three part lecture on metamaterials. Metamaterials are expected to open a gateway to unprecedented electromagnetic properties and functionality unattainable from naturally occurring materials, thus enabling a family of new “meta-devices”. In these three lectures, we review this new emerging field and significant progress in developing metamaterials. Specifically, we describe recently demonstrated artificial magnetism at high frequencies, including the visible part of the spectrum, negative-index in the optical range, and promising approaches along with challenges in realizing optical cloaking. The new paradigm of engineering space for light with transformation optics will be also discussed.

Data Science and Nanomanufacturing

Quantitative TEM/STEM Simulations

Single particle cryo-EM is revolutionizing structural biology. Many structures of viruses and protein complexes have been determined to 2-4 Å resolutions. While stable structures that can be expressed/purified in large quantities can be solved routinely, the dynamic compositions and…

Displays drain current as a function of source-drain voltage for different values of gate voltage, gate dimensions, substrate material, and oxide material in an n-type MOSFET.

Simulate 3D nanowire transport in the effective mass approximation with phonon scattering and 3D Poisson self-consistent solution

Compute the eigenstates of a particle in a box of various shapes including domes and pyramids.

Simulate Coulomb Blockade through Many-Body Calculations in a single and double quantum dot system