papers

Publications (12)

physics.ins-det2025

Linear and Nonlinear Ultra-Short Pulse Looped Antennas: Radiation and Parametric Oscillations

H. Grebel

Modern optical systems send and receive ultra-short temporal pulses (USP). While ultra-broad band antennas do exist in the microwave region (e.g., log-periodic antennas), their sho…

physics.optics2020

Optical cages made of graphitic frameworks

J. P. Walker, H. Grebel

In pursuit of infrared (IR) radiation absorbers, we examine quasicrystal structures made of graphite wires. An array of graphitic cages and cage-within-cage, and whose overall dime…

physics.chem-ph2022

Active-carbon based supercapacitors with Au colloids: the case for placing the colloids at the electrolyte/electrode interface

H. Grebel, Shupei Yu, Yuanwei Zhang

Supercapacitors (S-C) are short-term energy storage elements that find many applications, e.g., electronic charging devices and suppressors of power fluctuations in grids that are…

cond-mat.mes-hall2020

The effect of periodic spatial perturbations on the emission rates of quantum dots near graphene platforms

X. Miao, D. J. Gosztola, X. Ma +3

Quenching of fluorescence (FL) at the vicinity of conductive surfaces, and in particular, near a 2-D graphene layer has become an important biochemical sensing tool. The quenching…

cond-mat.mes-hall2021

Optically Controlled Supercapacitors with Semiconductor Embedded Active Carbon Electrodes

H. Grebel

Supercapacitors, S-C - capacitors that take advantage of the large capacitance at the interface between an electrode and an electrolyte - have found many short-term energy applicat…

physics.optics2018

Optical Cages

V. Kumar, J. P. Walker, H. Grebel

We examine array of metal-mesh frameworks for their wide-band absorption. These take the form of quasi-crystal optical cages. An array of cages tends to focus the incoming radiatio…

physics.chem-ph2025

Super-capacitors interfaced with quantum dots at the electrolyte/electrode interface: capacitance gain and fluorescence line-width narrowing

H. Grebel

Quantum dots (QDs), embedded in supercapacitors (S-C) cells exhibited capacitance amplification that peaked at certain QD concentration. More than 2.5 peak amplification was demons…

eess.SY2024

An Electrical Grid with Discrete Energy Levels

H. Grebel

Minimizing both power fluctuations and energy waste in an electrical grid is a central challenge to energy policy. Any discrepancy between power production and loads may lead to in…

cond-mat.mes-hall2023

Raman spectroscopy of active-carbon electrodes when Au colloids are placed at the electrolyte/electrode interface

H. Grebel, Y. Zhang

We use surface enhanced Raman spectroscopy (SERS) in studying functionalized Au nanoparticles (AuNPs) when incorporated in active-carbon (A-C) based super-capacitor cells. We obser…

physics.chem-ph2020

Asymmetric supercapacitors: optical and thermal effects when active carbon electrodes are embedded with nano-scale semiconductor dots

H. Grebel

Optical and thermal effects in asymmetric supercapacitors, whose active-carbon (AC) electrodes were embedded with nano-Si (n-Si) quantum dots (QD), are reported. We describe two st…

physics.app-ph2020

Parametric Oscillation and amplification with gate controlled capacitor-within-capacitor

H. Grebel

A Capacitor-within-Capacitor (CWC) is a nested electronic element that has two components: the cell (e.g., the outer capacitor) and the gate (e.g., the inner capacitor). The design…

physics.app-ph2018

Transfer of Graphene with Protective Oxide Layers

H. Grebel, L. Stan, A. V. Sumant +4

Transfer of graphene, grown by Chemical Vapor Deposition (CVD), to a substrate of choice, typically involves deposition of a polymeric layer (typically, poly(methyl methacrylate, P…