arXiv subjects

Daria Beznasyuk

Publications and source records attributed to Daria Beznasyuk.

3 recordsLinked to original sources

arXiv2026

Tomography of Transport Pathways in Selective-Area-Grown Nanowires Using Angle-Resolved Conductance Fluctuations

Understanding the spatial distribution of carriers is important for interpreting transport in nanoscale devices. Here, we apply conductance fluctuation tomography to planar selective-area-grown InAs nanowires in both normal-normal and normal-superconductor device geometries. By tracking the evolution of conductance-interference features as a function of magnetic-field strength and orientation, we extract information about the geometry of phase-coherent transport pathways. Using theory to distinguish between bulk-dominated transport, coherent near-surface transport across facets, and transport confined to individual facets. The measurements are consistent with transport dominated by a near-surface accumulation layer in InAs. Devices with normal contacts show behavior consistent with coherent transport across the nanowire apex, whereas hybrid normal-superconductor devices exhibit signatures of more facet-dependent transport. These results demonstrate how universal conductance fluctuations can be used as a tomographic probe of phase-coherent transport pathways in semiconductor nanostructures.

cond-mat.mes-hall↗

arXiv2025

$μ_\mathrm{2T}(n)$: A Method for Extracting the Density Dependent Mobility in Two-Terminal Nanodevices

Measuring carrier mobility as a function of the carrier density in semiconductors using Hall effect is the gold standard for quantifying scattering mechanisms. However, for nanostructures, the Hall effect is not applicable, and the density dependence of mobility is generally inaccessible, rendering Hall effect measurements impractical. Here, we present $μ_\mathrm{2T}(n)$, a new procedure allowing us to extract the density dependent mobility in two-terminal measured nano scale field effect transistors at zero magnetic field from conventional conductance vs gate voltage measurements. We validate $μ_\mathrm{2T}$ against standard Hall measurements and then apply the procedure to 256 individual two-terminal InAs nanowire FETs, extracting information about the scattering mechanisms. To illustrate its broad utility, we reanalyze published data in which mobility had been treated as density independent. Our method represents a new powerful tool for optimization and development of nanomaterials crucial for a wide range of new technologies.

cond-mat.mes-hall↗

arXiv2021

Selective Area Growth Rates of III-V Nanowires

Selective area growth (SAG) of semiconductors is a scalable method for fabricating gate-controlled quantum platforms. This letter reports on the adatom diffusion, incorporation, and desorption mechanisms that govern the growth rates of SAG nanowire (NW) arrays. We propose a model for the crystal growth rates that considers two parameter groups: the crystal growth control parameters and the design parameters. Using GaAs and InGaAs SAG NWs as platform we show how the design parameters such as NW pitch, width, and orientation have an impact on the growth rates. We demonstrate that by varying the control parameters (i.e. substrate temperature and beam fluxes) source, balance, and sink growth modes may exist in the SAG selectivity window. Using this model, we show that inhomogeneous growth rates can be compensated by tuning the design parameters.

cond-mat.mtrl-sci↗