arXiv subjects

G. S. Duesberg

Publications and source records attributed to G. S. Duesberg.

4 recordsLinked to original sources

arXiv2026

Strain control of mid-IR spectroscopic nonlinear photocurrents in PtSe$_2$

Semi-metallic noble-metal dichalcogenides are promising materials for infrared optoelectronics, yet the origin and tunability of their nonlinear optical responses remain poorly understood. Here, we demonstrate in-situ mechanical control of photon-drag photocurrents in polycrystalline PtSe$_2$ thin films grown on flexible polyimide substrates. Using polarization-resolved mid-infrared photocurrent spectroscopy under uniaxial tensile strain, we observe pronounced strain-dependent changes in resistivity, photoconductivity, and helicity-dependent nonlinear photocurrents. The spectral response is consistent with optical excitations across the spin-orbit-coupling-induced (SOC) band gap near the K point. We develop a theoretical framework attributing the photocurrent primarily to photon-drag induced by photon-momentum symmetry breaking. Strain modifies its magnitude and polarization dependence through deformation potentials that tune the SOC-induced band gap. These results establish mechanical strain as a route toward reconfigurable infrared polarization detection.

cond-mat.mtrl-sci↗

arXiv2004

Sub 20 nm Short Channel Carbon Nanotube Transistors

Carbon nanotube field-effect transistors with sub 20 nm long channels and on/off current ratios of > 1000000 are demonstrated. Individual single-walled carbon nanotubes with diameters ranging from 0.7 nm to 1.1 nm grown from structured catalytic islands using chemical vapor deposition at 700 degree Celsius form the channels. Electron beam lithography and a combination of HSQ, calix[6]arene and PMMA e-beam resists were used to structure the short channels and source and drain regions. The nanotube transistors display on-currents in excess of 15 microA for drain-source biases of only 0.4 Volt.

cond-mat.mtrl-sci↗

arXiv2004

Carbon Nanotubes in Microelectronic Applications

Carbon nanotubes with their outstanding electrical and mechanical properties are suggested as interconnect material of the future and as switching devices, which could outperform silicon devices. In this paper we will introduce nanotubes, specify the applications, where nanotubes can contribute to the advancement of Moore's law and show our progress of nanotube process integration in a microelectronic compatible way. The growth of single individual nanotubes at lithographically defined locations on whole wafers as a key requirement for the successful implementation of nanotubes is shown. In terms of nanotube transistors we propose a vertical nanotube transistor concept which outperforms the ITRS requirements for the year 2016. The performance is mainly limited by contact resistances, but by comparison with silicon devices we show that fabricated nanotube transistors already today exceed the values for transconductance, on-resistance and drive current of silicon devices.

cond-mat.mtrl-sci↗

arXiv2004

Bias Dependence and Electrical Breakdown of Small Diameter Single-Walled Carbon Nanotubes

The electronic breakdown and the bias dependence of the conductance have been investigated for a large number of catalytic chemical vapor deposition (CCVD) grown single-walled carbon nanotubes (SWCNTs) with very small diameters. The convenient fabrication of thousands of properly contacted SWCNTs was possible by growth on electrode structures and subsequent electroless palladium deposition. Almost all of the measured SWCNTs showed at least weak gate dependence at room temperature. Large differences in the conductance and breakdown behavior have been found for "normal" semiconducting SWCNTs and small band-gap semiconducting (SGS) SWCNTs.

cond-mat.mtrl-sci↗