Epitaxial Growth of Room-Temperature Ferromagnetic MnAs Segments on GaAs Nanowires via Sequential Crystallization

Abstract

Nanowire geometry and crystalline structure under Mn supply Figure S1(a) and S1(b) show scanning electron microscopy (SEM) images of regular, Mn-free GaAs nanowires, grown as a control experiment, and nanowires grown under (Ga,Mn)Assupply ( rst sample series described in the article). On both samples the wires display the same length, indicating that the supply of Mn does not inhibit the VLS growth mechanism.The only di erence visible in SEM concerns the catalyst droplet: solidi ed Ga-droplets are perfectly spherical ( Figure S1(a)), while solidi ed (Ga,Mn)-alloy droplets are partially faceted ( Figure S1(b)). The results obtained in SEM for the second sample series described in the article (GaAs NWs with liquid Ga droplet exposed to Mn) are identical to Figure S1(b). The results obtained in SEM for the third sample series (GaAs NWs exposed to Mn 1

Magnetic Force Sensing Using a Self-Assembled Nanowire

“…It has been shown by high-resolution transmission electron microscopy that this growth process leads to the formation of a well-defined hexagonal α-MnAs wurzite crystal at the tip of a predominantly wurzite GaAs NW, with an epitaxial relationship [0001]MnAs [0001]GaAs along the NW-axis [22]. As reported for bulk MnAs, the tip is in a hexagonal ferromagnetic α-phase up to the Curie temperature of about 313 K, above which it undergoes a structural phase transition into an orthorhombic paramagnetic β-phase [23].…”

Growth and properties of self‐catalyzed (In,Mn)As nanowires

“…Similar to thin films, the most attention has been paid to the study of the growth of the NWs based on (Ga,Mn)As DMS. They have been obtained using a variety of catalysts for the growth, such as MnAs , Ga , Mn , as well as by overgrowth of wrapped shell on GaAs NWs and by Mn ion implantation . It should be noted, that usually the formation of (Ga,Mn)As shell carries out at lower temperatures .…”

“…At the same time, the use of Ga or Mn assisted synthesis of (Ga,Mn)As NWs allows to increase the growth temperature and, as consequence, the crystalline quality of the structures. Nonetheless, for the NWs grown by Ga‐assisted molecular‐beam epitaxy (MBE), it was found that Mn atoms had been accumulated in the Ga droplet . Moreover, no significant incorporation of Mn atoms into the nanowire was observed , although residual doping level had not been determined.…”

“…Nonetheless, for the NWs grown by Ga‐assisted molecular‐beam epitaxy (MBE), it was found that Mn atoms had been accumulated in the Ga droplet . Moreover, no significant incorporation of Mn atoms into the nanowire was observed , although residual doping level had not been determined. In turn, the investigation of (Ga,Mn)As NWs obtained by Mn‐assisted MBE has shown that Mn doping level is about 1 × 10 18 cm –3 .…”

Синтез и исследование электрических свойств диарсенида трикадмия с наногранулами MnAs

“…Соединение MnAs обладает ферромагнетизмом с температурой Кюри немного выше комнатной (318 K), что делает его перспективным материалом для использования в различных элементах спиновой электроники, функционирующих в терагерцовом диапазоне [8][9][10].…”