Morphological instability of epitaxially stressed quantum ringsJ. Colin
PHYMAT-CNRS UMR 6630, Université de Poitiers - BP 30179, 86962 Futuroscope Cedex, France, EU
received 1 September 2009; accepted in final form 12 November 2009; published December 2009
published online 10 December 2009
The size and morphological instability of a heteroepitaxially stressed ring of constant height and constant area is theoretically investigated through a static calculation of the edge and elastic energy terms. It is shown that above a critical value of stress, the formation of a ring-shaped nanostructure of selected width is favoured compared to a circular island of the same area. It is then found that in-phase fluctuations of both ring edges may preferentially develop leading to serpentine shape. When the ring width increases and its radii decrease, the possibility of development of anti-phase fluctuations leading to the formation of more complicated shape is discussed.
62.25.-g - Mechanical properties of nanoscale systems.
68.35.Ct - Interface structure and roughness.
68.65.Hb - Quantum dots (patterned in quantum wells).
© EPLA 2009