arXiv subjects

Eriks Dipans

Publications and source records attributed to Eriks Dipans.

3 recordsLinked to original sources

arXiv2026

Growth and characterization of GaN/Ga2O3 Nanowire Heterostructures for Ultraviolet Optoelectronics

Ultraviolet-range GaN/b-Ga2O3 heterostructures were fabricated and investigated in both planar and nanowire geometries using pulsed laser deposition and reactive magnetron sputtering from a liquid gallium target for b-Ga2O3 deposition, while both GaN nanowire arrays and planar p-type Mg-doped GaN layers were grown by metal-organic chemical vapor deposition. Precise control of film uniformity and thickness was achieved as confirmed by structural and morphology studies using X-ray diffraction, X-ray photoelectron spectroscopy, atomic force microscopy and scanning electron microscopy. Planar n-Ga2O3/p-GaN heterojunction diodes were electrically and photoelectronically characterized, exhibiting pronounced rectifying behavior, high forward current and a visible-blind ultraviolet photoresponse under zero external bias, demonstrating intrinsic self-powered operation. Furthermore, GaN/b-Ga2O3 core/shell nanowire heterostructures were developed and systematically studied with a focus on morphology control and process optimization. The influence of deposition parameters on shell thickness, uniformity, and tapering was investigated, enabling improved conformality of the b-Ga2O3 coating on the M-plane facets of GaN nanowires. The results highlight the viability of physical vapor deposition techniques for forming GaN/b-Ga2O3 heterostructures and establish a pathway toward nanowire-based ultraviolet optoelectronic devices.

cond-mat.mtrl-sci↗

arXiv2026

Thin amorphous molybdenum silicide superconducting shells around individual nanowires deposited via magnetron co-sputtering

Employing amorphous superconductors, such as Type-II molybdenum silicide (MoSi), instead of crystalline materials significantly simplifies the material deposition and scalable nanoscale prototyping, beneficial for quantum electronic and photonic device fabrication. In this work, deposition of amorphous superconductive MoSi thin films on flat and nanowire (NW) substrates was demonstrated via pulsed direct-current magnetron co-sputtering from molybdenum and silicon targets in an argon atmosphere. MoSi films were deposited on oxidized silicon wafers and Ga2O3 NWs with 6 nm Al2O3 insulating shell, grown around the NWs using atomic layer deposition, and studied using scanning and transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Four-point Cr/Au electrical contacts were defined on the thin films and on individual Ga2O3-Al2O3-MoSi core-shell NWs using lithography for low-temperature electrical measurements. By controlling the sputtering power of the targets and thus adjusting the molybdenum-to-silicon ratio in the MoSi films, their properties were optimized to achieve critical temperature Tc of 7.25 K. Such superconducting shell NWs could provide new avenues for fundamental studies and interfacing with other materials for quantum device applications.

cond-mat.supr-con↗

arXiv2025

MoSe2 and WSe2 shell morphology control via temperature optimization during two-step growth of ZnSe-based core-shell nanowires

Achieving uniform and controlled transition metal dichalcogenide (TMD) shell growth on nanowires (NWs) remains a key challenge, limiting the development of high-quality core-shell heterostructures for optoelectronic and photocatalytic applications. In this work, the fabrication of ZnSe-MoSe2 and ZnSe-WSe2 core-shell NWs was successfully demonstrated. ZnSe NWs were grown via the vapor-liquid-solid growth mechanism, while TMD (MoSe2 or WSe2) shells were formed through a two-step process of sacrificial oxide layer deposition via magnetron sputtering followed by selenization process in a chemical vapor transport reactor. As-grown nanostructures were characterized using X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and photoluminescence spectroscopy. It was observed that the TMD shell morphology can be controlled through the selenization process temperature optimization, which arises due to different growth mechanisms discussed here. The studied trends could be further extended to other semiconductor NW and TMD core-shell heterostructure growth, offering promising avenues for advanced nanoscale applications.

cond-mat.mtrl-sci↗