Evidence of Cd1−xMnxS nanocrystal growth in a glass matrix by the fusion method

Abstract

In this work, CdS nanocrystals (NCs) doped with Mn were synthesized in a glass matrix by fusion. The as-grown Cd1−xMnxS NCs were investigated by optical absorption, atomic force microscopy, and electron paramagnetic resonance (EPR). The incorporation of Mn2+ ions in CdS NCs was confirmed by an absorption transition blueshift with increasing Mn concentration x. EPR spectra demonstrated the existence of two distinct Mn2+ ion locations: one incorporated in the core and the other near the surface of the Cd1−xMnxS NCs. The hyperfine interaction constants used to simulate the EPR spectra were A=7.6 and 8.2 mT, respectively. The synthesis of high quality Cd1−xMnxS NCs may allow the control of optical and magnetic properties.

Dilute magnetism in Zn1−xMnxTe nanocrystals grown in a glass template

“…In the presence of the hyperfine interaction, each Mn sixplet level, associated to the magnetic numbers M S = ±5/2, ±3/2, ±1/2 splits into an additional six levels identified by the nuclear magnetic quantum numbers, M I = ±5/2, ±3/2, ±½. The six strongest lines observed in the EPR spectra of Figure 4 are due to the resonance associated to the dipole-allowed DM S = ±1 with DM I = 0 [3], as shown schematically in the inset of Figure 4 where S = 1/2. Certainly, theses resonances attest to Mn 2+ incorporation in the core region of the ZnTe NCs.…”

“…Finally, as a result of the thermal annealing, dilute Zn 1Àx Mn x Te NCs were formed in the PZABP matrix. Other details on the nanoparticles growth in glass matrices by the fusion method can be found in literature [3,[13][14][15].…”

“…describes the Zeeman interaction with l e , g e , andB representing the Bohr magneton, the Landé g-factor and the magnetic field strength, respectively [3,13,[21][22][23][24]. The term,…”

“…This Letter provides evidence of Zn 1Àx Mn x Te NC growth, synthesized by fusion in a glass template allowing control of optical, morphological and magnetic properties as a function of magnetic ion concentration, x. The d-atomic sublevel of a Mn 2+ ion, with spin S = 5/2, acts as a paramagnetic center which has exchange interactions with the sp-hybridized electron states of surrounding magnetic ions [2,3]. Besides temperature and magnetic field sensitivity, this sp-d exchange interaction is also strongly dependent on Mn ion concentration [7,10].…”

“…These structures are also good candidates for quantum computation, spin filters and quantum information, and other spintronic devices [2][3][4]. In this context, ZnTe and Zn 1Àx Mn x Te semiconductors, with or without quantum confinement properties, have been synthesized by various methods, such as mechanical alloying [5], colloidal [6], hot wall epitaxy [7], and molecular beam epitaxy [1,8,9].…”