Quasi-one-dimensional single AlGaAs/GaAs Hall bar quantum wires grown on patterned substrates

Abstract

Hall bars with widths down to about 250 nm were prepared by overgrowth on patterned GaAs(001) substrates using molecular beam epitaxy. This fabrication method generates a lateral confinement potential determined by AlGaAs barriers. The four-terminal magnetoresistance of a single wire, measured at 1.3 K after illumination, displays the well-known features of quasi-one-dimensional electron systems. We estimate the electron mobility in a ∼250 nm wide wire to be larger than 51 000 cm2/V s at a carrier concentration of 3.3×1011 cm−2.This mobility is comparable to the one measured in a wide reference sample fabricated under identical conditions.

In situ etching and regrowth in III–V molecular beam epitaxy for future nanotechnology

“…This method was already successfully used to produce quantum wires. [4][5][6] The problem, however, is the growth of welldefined and reproducible narrow plateaus due to an extreme sensitivity of the plateau width on the growth parameters and the width of the initial mesa stripe. Another way is the growth of the ridge which forms a round shaped tip with a curvature radius of about 20-30 nm.…”

Magnetosubband and edge state structure in cleaved-edge overgrown quantum wires in the integer quantum Hall regime

“…At the same time the rigorous theory for edge-state structure in hard-wall quantum wires accounting for electron-electron interaction and spin effects has not been reported yet. Such a theory is obviously required for a detailed analysis of recent experiments on cleaved-edge overgrown sharp-edge wires and 2DEGs 2,3,4,5,6,7,8 .…”

“…The molecular beam epitaxy double-growth technique 3 (often referred to as a cleaved-edge overgrowth) since early 1990-th has become one of the most widely-used techniques for fabrication of quantum wires 4,5,6 and twodimensional electron gases (2DEGs) 7 with an essentially hard wall confinement with the atomic precision. Quantum wires with a steep confinement can also be fabricated by overgrowth on patterned GaAs(001) substrates using molecular beam epitaxy 8 .…”

“…At the same time the rigorous theory for edge-state structure in hard-wall quantum wires accounting for electron-electron interaction and spin effects has not been reported yet. Such a theory is obviously required for a detailed analysis of recent experiments on cleaved-edge overgrown sharp-edge wires and 2DEGs 2,3,4,5,6,7,8 . Motivated by the above-mentioned experimental stud-ies, in this paper we present a detailed theory of magnetosubband and edge state structure in quantum wires with a hard wall confinement taking into account electronelectron interaction including exchange and interaction effects.…”

Solid-immersion photoluminescence microscopy of carrier diffusion and drift in facet-growth GaAs quantum wells

“…Facet epitaxial growth on patterned substrates is a promising method to fabricate self-formed damage-free modulated semiconductor structures, 1-3 such as quantum wires, quantum dots, micro-optical waveguides including lasers, 2,4 and electron transport devices. 5,6 To establish facet growth techniques and to optimize growth conditions, characterization of spatial variation or uniformity of electronic or optical properties in the formed structures is important. Moreover, carrier distribution, diffusion, and drift in low-dimensional structures are essential subjects both in fundamental physics and in device performance.…”