| Autor: |
Lad, Amit D., Rajesh, Ch., Khan, Mahmud, Ali, Naushad, Gopalakrishnan, I. K., Kulshreshtha, S. K., Mahamuni, Shailaja |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 5/15/2007, Vol. 101 Issue 10, p103906, 5p, 1 Chart, 4 Graphs |
| Abstrakt: |
Magnetic properties of manganese-doped ZnSe quantum dots with the size of approximately 3.6 nm are investigated. The amount of Mn in the ZnSe quantum dots has been varied from 0.10% to 1.33%. The doping level in the quantum dots is much less than that used in the precursor. The co-ordination of Mn in the ZnSe lattice has been determined by electron paramagnetic resonance (EPR). Two different hyperfine couplings 67.3×10-4 and 60.9×10-4 cm-1 observed in the EPR spectrum imply that Mn atoms occupy two distinct sites; one uncoordinated (near the surface) and other having a cubic symmetric environment (nanocrystal core), respectively. Photoluminescence measurements also confirm the incorporation of Mn in ZnSe quantum dots. From the Curie-Weiss behavior of the susceptibility, the effective Mn-Mn antiferromagnetic exchange constant (J1) has been evaluated. The spin-glass behavior is observed in 1.33% Mn-doped ZnSe quantum dots, at low temperature. Magnetic behavior at a low temperature is discussed. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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