Vega-Flick, Alejandro Jung, Daehwan Yue, Shengying Bowers, John E. Liao, Bolin 2024-01-19T20:32:08Z 2024-01-19T20:32:08Z 2021-09-02 2019-03-11 2475-9953 https://pubs.kist.re.kr/handle/201004/120219 Epitaxial growth of III-V semiconductors on Si is a promising route for silicon photonics. Threading dislocations and the residual thermal stress generated during growth are expected to affect the thermal conductivity of the III-V semiconductors, which is crucial for efficient heat dissipation from photonic devices built on this platform. In this work, we combine a noncontact laser-induced transient thermal grating technique with ab initio phonon simulations to investigate the in-plane thermal transport of epitaxial GaAs-based buffer layers on Si, employed in the fabrication of III-V quantum dot lasers. Surprisingly, we find a significant reduction of the in-plane thermal conductivity of GaAs, up to 19%, as a result of a small in-plane biaxial stress of similar to 250 MPa. Using ab initio phonon calculations, we attribute this effect to the enhancement of phonon-phonon scattering caused by the in-plane biaxial stress, which breaks the cubic crystal symmetry of GaAs. Our results indicate the importance of eliminating the residual thermal stress in the epitaxial III-V layers on Si to avoid the reduction of thermal conductivity and facilitate heat dissipation. Additionally, our results showcase potential means of effectively controlling thermal conductivity of solids with external strain/stress. English AMER PHYSICAL SOC QUANTUM-DOT LASERS TOTAL-ENERGY CALCULATIONS AB-INITIO FILMS TRANSPORT DYNAMICS GROWTH Reduced thermal conductivity of epitaxial GaAs on Si due to symmetry-breaking biaxial strain Article 10.1103/PhysRevMaterials.3.034603 1 PHYSICAL REVIEW MATERIALS, v.3, no.3 PHYSICAL REVIEW MATERIALS 3 3 scie scopus 000461076800004 2-s2.0-85063000630 Materials Science, Multidisciplinary Materials Science Article QUANTUM-DOT LASERS TOTAL-ENERGY CALCULATIONS AB-INITIO FILMS TRANSPORT DYNAMICS GROWTH