Quantum confinement of Bi2S3 in glass with magnetic behavior

Abstract

The novel Bi2S3 quantum dots (QDs) glass nanosystems with unique magnetic properties have been investigated. The monodispersed QDs of size in the range of 3 to 15 nm were grown in the glass matrix. The optical study of these nanosystems clearly demonstrated the size quantization effect resulting in a pronounced band gap variation with QD size. The magnetic properties of the pristine glass and the Bi2S3 QD glass nanosystems were investigated by VSM and SQUID magnetometer. The pristine glass did not show any ferromagnetism while the Bi2S3 glass nanosystems showed significant and reproducible ferromagnetism. We also investigated the effect of the size of Bi2S3 QDs on the magnetic properties. The saturation magnetization for the 15 nm QD glass-nanosystem (124 memu/g) was observed to be higher as compared to the 3nm QD glass nanosystem (58.2 memu/g). The SQUID measurement gave the excellent hysteresis up to 300K. Surprisingly, the bulk Bi2S3 powder is diamagnetic in nature but Bi2S3 quantum dots glass nanosystem showed the ferromagnetic behavior for the first time. The investigated novel QD glass-nanosystem may have a potential application in spintronic devices and most importantly, this nanosystem can be fabricated in any usable shape as per the device requirement.

Coexistence of superconductivity and ferromagnetism in Sr0.5Ce0.5FBiS2

“…3(a). A rapid increase in the magnetic susceptibility and the obvious separation between ZFC and FC curves below 7.5 K may be ascribed to the long-range FM order of the Ce 4f ions, or the possible small ferromagnetic clusters 30 . With further cooling down, an obvious drop around 2.8 K in both the ZFC and FC data is observed owing to the superconducting screening and Messier effect, respectively.…”

Synthesis Process Controlled of Semimagnetic Bi2–xMnxS3 Nanocrystals in a Host Glass Matrix

“…Contrasts in the MFM images are caused by the incorporation of Mn 2+ ions into the crystalline structure of the Bi 2 S 3 nanocrystals and indicate that the nanocrystals are magnetic. Recent studies have shown that nanosized Bi 2 S 3 semiconductors behave ferromagnetically, 17 whereas the bulklike Bi 2 S 3 behaves diamagnetically. Figure 2a shows a low intensity contrast in the magnetic phase images (right panel), indicating that the Bi 2 S 3 nanocrystals behave magnetically.…”

Doping-Concentration-Induced Ferromagnetism and Antiferromagnetism in In2S3:Dy3+ Quantum Dots

“…Nanoscale magnetism plays an increasingly significant role in new generation magnetic storage devices and microelectronic industries. − Especially some novel materials with Curie temperatures ( T c ) well in excess of room temperature and high saturation magnetization (Ms) remain a continuous priority. − Diluted magnetic semiconductor (DMS) quantum dots (QDs) , meet the aforementioned needs and have attracted considerable attention owing to their remarkable magneto-optical effect and three-dimensional quantum confinement of electrons and holes in recent years. − It opens the prospect of combining information processing and storage functionalities in one material and has potential applications in the emerging field of spin-based electronics or spintronics, , such as miniaturization of electronic devices, high density data storage systems, and magnetic fluids. − Nowadays, much effort has been devoted to the exploration of these new DMS nanomaterials to achieve their practical applications, which at the same time provide precise and insightful guidance for designing and synthesizing unique spintronic materials. − …”