Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Physics

Excess Electron Screening Of Remote Donors And Mobility In Modern Gaas/Algaas Heterostructures, M. Sammon, Tianran Chen, B. I. Shklovskii Oct 2018

Excess Electron Screening Of Remote Donors And Mobility In Modern Gaas/Algaas Heterostructures, M. Sammon, Tianran Chen, B. I. Shklovskii

Physics & Engineering Faculty Publications

In modern GaAs/AlxGa1−xAs heterostructures with record high mobilities, a two-dimensional electron gas (2DEG) in a quantum well is provided by two remote donor δ-layers placed on both sides of the well. Each δ-layer is located within a narrow GaAs layer, flanked by narrow AlAs layers which capture excess electrons from donors but leave each of them localized in a compact dipole atom with a donor. Still excess electrons can hop between host donors to minimize their Coulomb energy. As a result they screen the random potential of donors dramatically. We numerically model the pseudoground state of excess electrons at a …


Measuring The Practical Particle-In-A-Box: Orthorhombic Perovskite Nanocrystals, Brandon Mitchell, Eric Herrmann, Junhao Lin, Leyre Gomez, Chris De Weerd, Yasufumi Fujiwara, Kazutomo Suenaga, Tom Gregorkiewicz Sep 2018

Measuring The Practical Particle-In-A-Box: Orthorhombic Perovskite Nanocrystals, Brandon Mitchell, Eric Herrmann, Junhao Lin, Leyre Gomez, Chris De Weerd, Yasufumi Fujiwara, Kazutomo Suenaga, Tom Gregorkiewicz

Physics & Engineering Faculty Publications

A connection between condensed matter physics and basic quantum mechanics is demonstrated as we use the fundamental 3D particle-in-a-box model to explain the optical properties of semiconductor nanocrystals, which are substantially modified due to quantum confinement. We also discuss recent advances in the imaging and measurement capabilities of transmission electron microscopy, which have made it possible to directly image single nanocrystals while simultaneously measuring their characteristic absorption energies. We introduce the basic theory of nanocrystals and derive a simplified expression to approximate the optical bandgap energy of an orthorhombic nanocrystal. CsPbBr3 perovskite nanocrystals are used to demonstrate this model due …


E. Coli Elongation Factor Tu Bound To A Gtp Analogue Displays An Open Conformation Equivalent To The Gdp-Bound Form, Jesper S. Johansen, Darius Kavaliauskas, Shawn H. Pfeil, Mickael Blaise, Barry C. Cooperman, Yale E. Goldman, Søren S. Thirup, Charlotte R. Knudsen Aug 2018

E. Coli Elongation Factor Tu Bound To A Gtp Analogue Displays An Open Conformation Equivalent To The Gdp-Bound Form, Jesper S. Johansen, Darius Kavaliauskas, Shawn H. Pfeil, Mickael Blaise, Barry C. Cooperman, Yale E. Goldman, Søren S. Thirup, Charlotte R. Knudsen

Physics & Engineering Faculty Publications

According to the traditional view, GTPases act as molecular switches, which cycle between distinct ‘on’ and ‘off’ conformations bound to GTP and GDP, respectively. Translation elongation factor EF-Tu is a GTPase essential for prokaryotic protein synthesis. In its GTP-bound form, EF-Tu delivers aminoacylated tRNAs to the ribosome as a ternary complex. GTP hydrolysis is thought to cause the release of EF-Tu from aminoacyl-tRNA and the ribosome due to a dramatic conformational change following Pi release. Here, the crystal structure of Escherichia coli EF-Tu in complex with a non-hydrolysable GTP analogue (GDPNP) has been determined. Remarkably, the overall conformation of EF-Tu·GDPNP …


A Fan-Tastic Quantitative Exploration Of Ohm's Law, Brandon Mitchell, Robert Ekey, Roy Mccullough, William Reitz Feb 2018

A Fan-Tastic Quantitative Exploration Of Ohm's Law, Brandon Mitchell, Robert Ekey, Roy Mccullough, William Reitz

Physics & Engineering Faculty Publications

No abstract provided.