Growth evolution and magneto-optical characteristics of self-assembled ZnTe/ZnMnSe quantum dots

• Published in: Journal of crystal growth 2013-09, Vol.378, p.222-225
• Main Authors: Lee, Ling, Fan, Wen-Chung, Chien, Kun-Feng, Tzou, An-Jye, Chou, Wu-Ching
• Format: Article
• Language: English
• Subjects: A1. Nanostructures; A3. Molecular beam epitaxy; B1. Zinc compounds; B2. Magneto-optic materials; Cross-disciplinary physics: materials science; rheology; Crystal growth; Density; Evolution; Exact sciences and technology; Magnetic fields; Materials science; Methods of crystal growth; physics of crystal growth; Methods of nanofabrication; Molecular beam epitaxy; Monolayers; Nanoscale materials and structures: fabrication and characterization; Other topics in nanoscale materials and structures; Physics; Quantum dots; Self-assembly; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Zinc tellurides
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2012.11.009

The growth evolution and the magneto-optical characteristics of the self-assembled single-layer ZnTe/ZnMnSe quantum dots grown by molecular beam epitaxy were investigated. As the ZnTe coverage is above 2.0 monolayers, a Stranski–Krastanov growth process is observed with a significantly increased dot density on top of two-dimensional plateaus. As the coverage exceeds 2.7 monolayers, ripened dots dominate instead. Furthermore, a saturated degree of circular polarization of 76% at applied magnetic field of 4T and the formation of magnetic polarons with a formation time of 7.4ns were demonstrated. ► Size of self-assembled ZnTe QD on ZnMnSe was controlled by tuning coverage. ► Stranski–Krastanov and ripened process occur as coverage exceeds 2.0 and 2.7ML, respectively. ► QD system shows a strong degree of polarization and the formation of magnetic polarons.