tailieunhanh - Báo cáo hóa học: " Anisotropic Confinement, Electronic Coupling and Strain Induced Effects Detected by Valence-Band Anisotropy in Self-Assembled Quantum Dots"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: IAnisotropic Confinement, Electronic Coupling and Strain Induced Effects Detected by Valence-Band Anisotropy in Self-Assembled Quantum Dots | Villegas-Lelovsky et al. Nanoscale Res Lett 2011 6 56 http content 6 1 56 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Anisotropic Confinement Electronic Coupling and Strain Induced Effects Detected by Valence-Band Anisotropy in Self-Assembled Quantum Dots L I I r- I S-. I f r Izx Ĩ 1 2h ỉ Ch I Y 1 3 I f ĩ D I r s r r l 1 I ỉ r I 1 4 IV I I z- I- i - r-4 C h ỉ v z s I V-3 5 D I I I n z i 3 7 viiiegas-LeiovsKy MD leodoro V Lopez-Richard C Calseverino A ivididCnidS E Marega Jr BL Liang Yu I Mazur3 GE Marques1 C Trallero-Giner6 GJ Salamo3 Abstract A method to determine the effects of the geometry and lateral ordering on the electronic properties of an array of one-dimensional self-assembled quantum dots is discussed. A model that takes into account the valence-band anisotropic effective masses and strain effects must be used to describe the behavior of the photoluminescence emission proposed as a clean tool for the characterization of dot anisotropy and or inter-dot coupling. Under special growth conditions such as substrate temperature and Arsenic background 1D chains of As quantum dots were grown by molecular beam epitaxy. Grazing-incidence X-ray diffraction measurements directly evidence the strong strain anisotropy due to the formation of quantum dot chains probed by polarization-resolved low-temperature photoluminescence. The results are in fair good agreement with the proposed model. Introduction Recent attention has been given to the study of coupled quantum dot QD arrays for their potential application in quantum information processing 1-3 . The selfassembling process and its control become essential concerns in the search for new proposals of optoelectronic and quantum computing devices. Also the spinor states in quasi-zero dimensional systems and their electronics have become features of renewed interest 4-7 . High uniformity of size shape and distribution control of dot arrays are required