arXiv subjects

C. M. Krowne

Publications and source records attributed to C. M. Krowne.

4 recordsLinked to original sources

arXiv2019

Graphyne and Borophene as Nanoscopic Materials for Electronics

Discussions based upon rigorous derivations show the validity range of the analogy between solid state materials like graphene which possess K symmetry crystallographic points in k-space, and the relativistic solutions for massive and low mass particles associated with the Dirac equation. Both eigenenergies and eigenvectors are examined for the nonrelativistic solutions of the Schrodinger equation using the tight-binding method, and the relativistic solutions of the Dirac equation. Implications for exploring new materials are drawn from the results. It is concluded Dirac materials are unlikely to fulfill the needs of transistor action materials, but two prime candidates which may satisfy those needs for 2D future electronics are proposed, graphyne and borophene.

physics.app-ph↗

arXiv2015

Functionalized graphene as a model system for the two-dimensional metal-insulator transition

Reports of metallic behavior in two-dimensional (2D) systems such as high mobility metal-oxide field effect transistors, insulating oxide interfaces, graphene, and MoS2 have challenged the well-known prediction of Abrahams, et al. that all 2D systems must be insulating. The existence of a metallic state for such a wide range of 2D systems thus reveals a wide gap in our understanding of 2D transport that has become more important as research in 2D systems expands. A key to understanding the 2D metallic state is the metal-insulator transition (MIT). In this report, we demonstrate the existence of a disorder induced MIT in functionalized graphene, a model 2D system. Magneto-transport measurements show that weak-localization overwhelmingly drives the transition, in contradiction to theoretical assumptions that enhanced electron-electron interactions dominate. These results provide the first detailed picture of the nature of the transition from the metallic to insulating states of a 2D system.

cond-mat.mes-hall↗

arXiv2005

Guided Wave Propagation in Left-Handed Microstrip Structure Using Dispersive SRR Metamaterial

SRR metamaterial is used as a substrate material in a microstrip guided wave structure to determine what the effect is of a material with potentially excessive dispersion or loss or both. A Green's function method readily incorporates the metamaterial permittivity and permeability tensor characteristics. Ab initio calculations are performed to obtain the dispersion diagrams of several complex peopagation constant modes of the structure. Analytical analysis is done for the design and interpretation of the results, which demonstrate remarkable potential for realistic use in high frequency electronics.

cond-mat.mtrl-sci↗

arXiv2003

Restricted equivalence of paired epsilon-negative and mu-negative layers to a negative phase-velocity material ({\em alias} left-handed material)

The time-harmonic electromagnetic responses of (a) a bilayer made of an epsilon-negative layer and a mu-negative layer, and (b) a single layer of a negative phase-velocity material are compared. Provided all layers are electrically thin, a restricted equivalence between (a) and (b) exists. The restricted equivalence depends on the linear polarization state and the transverse wavenumber. Implications for perfect lenses and parallel-plate waveguides are considered.

physics.class-ph↗