Magneto-Optical Studies of HgTe/HgxCd1−xTe(S) Core-Shell Nanocrystals

Institute of Physical Chemistry, University of Hamburg, Hamburg, Hamburg, Germany
ChemPhysChem (Impact Factor: 3.42). 11/2003; 4(11):1203-10. DOI: 10.1002/cphc.200300809
Source: PubMed


The synthesis and magneto-optical properties of HgTe nanocrystals capped with HgxCd1-xTe(S) alloyed shells have been investigated. The magneto-optical measurements included the use of optically detected magnetic resonance (ODMR) and circular polarized photoluminescence (CP-PL) spectroscopy. The PL spectra suggest the existence of luminescence events from both the core HgTe and the HgxCd1-xTe(S) shells. The continuous-wave (cw) and time-resolved ODMR measurements revealed that the luminescence at the shell regime is associated with a trap-to-band recombination emission. The electron trap is comprised of a Cd-Hg mixed site, confirming the existence of an alloyed HgxCd1-xTe(S) composition. The ODMR data and the CP-PL measurements together revealed the g-values of the trapped electron and the valence band hole.

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