Physics Commons^™

Quantum Entanglement Of One-Dimensional Spinless Fermions, Emanuel Casiano-Diaz

Graduate College Dissertations and Theses

The constituents of a quantum many-body system can be inextricably linked, a phenomenon known as quantum entanglement. Entanglement can be used as a resource for quantum computing, quantum communication and detecting phase transitions, among others. The amount of entanglement can be quantified via the von Neumann and Rényi entropies, which have their origins in information theory.

In this work, the quantum entanglement between subsystems of a one dimen- sional lattice model of fermions is quantified. The von Neumann and Rényi entropies were calculated for two types of subsystems. In the first study, the subsystems were treated as two subsets of …

Polarization Charge Density In Strained Graphene, Noah Wilson

Graduate College Dissertations and Theses

Graphene, the world's first truly two-dimensional material, is unique for having an electronic structure described by an effective Lorentz invariant theory. One important consequence is that the ratio or Coulomb energy to kinetic energy is a constant, depending only on conditions within the lattice rather than on the average charge density as in a typical Galilean invariant material. Given this unusual property, a natural question would be how do phenomena, such as screening of a Coulomb impurity, happen in graphene? Moreover, how does the addition of uniaxial strain enhance or diminish this behavior? Here I discuss our work to calculate …

The Invention Of The Transistor, Bret E. Crawford

Graduate College Dissertations and Theses

Julius E. Lilienfeld filed for patents for three different designs for solid-state amplifying devices between 1926 and 1928, well before Bell Lab's discovery of the point-contact transistor in 1948. The American Physical Society named a prize in honor of Lilienfeld after receiving a substantial sum of money in 1982 from the will of his wife, Beatrice Lilienfeld, who believed her husband had not received sufficient credit for his scientific contributions. In order to investigate Lilienfeld's contribution to early efforts to replace the vacuum triode, we present the history surrounding these efforts, contributions and limitations of Lilienfeld's work, and details of …