The effect of the long-range order in a quantum dot array on the in-plane lattice thermal conductivity

✍ Scribed by A. Khitun; A. Balandin; J.L. Liu; K.L. Wang

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 98 KB
• Volume: 30
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.2001.0981

✦ Synopsis

Semiconductor quantum dot superlattices consisting of arrays of quantum dots have shown great promise for a variety of device applications, including thermoelectric power generation and cooling. In this paper we theoretically investigate the effect of long-range order in a quantum dot array on its in-plane lattice thermal conductivity. It is demonstrated that the long-range order in a quantum dot array enhances acoustic phonon scattering and, thus leads to a decrease of its lattice thermal conductivity. The decrease in the ordered quantum dot array, which acts as a phonon grating, is stronger than that in the disordered one due to the contribution of the coherent scattering term. The numerical calculations were carried out for a structure that consists of multiple layers of Si with layers of ordered Ge quantum dots separated by wetting layers and spacers.