Photoelastic properties of zinc-blende (AlGa)N in the UV: picosecond ultrasonic studies

Whale, Josh; Akimov, Andrey V.; Novikov, Sergei V.; Mellor, Christopher J.; Kent, Anthony J.

Abstract

Picosecond ultrasonics was used to study the photoelastic properties of zinc-blende (cubic) c-AlₓGa₁₋ₓN with x around 0.5 The velocities for longitudinal sound in the alloys were measured using ultrafast UV pump-probe experiments with (AlGa)N membranes. Strong Brillouin oscillations were observed in the (AlGa)N films attached to GaAs substrates. These oscillations are due to the dynamical interference of the probe beams reflected from the sample surface and interfaces and a picosecond-duration strain pulse propagating in the alloy layer. Optical and elasto-optical parameters including the complex refractive index and the fundamental band gap of the cubic nitride alloys are determined and compared with the values obtained by ellipsometry.

Citation

Whale, J., Akimov, A. V., Novikov, S. V., Mellor, C. J., & Kent, A. J. (2018). Photoelastic properties of zinc-blende (AlGa)N in the UV: picosecond ultrasonic studies. Physical Review Materials, 2(3), https://doi.org/10.1103/PhysRevMaterials.2.034606

• Journal Article Type: Article
• Acceptance Date: Feb 21, 2018
• Publication Date: Mar 29, 2018
• Deposit Date: Mar 2, 2018
• Publicly Available Date: Mar 29, 2018
• Journal: Physical Review Materials
• Electronic ISSN: 2475-9953
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 2
• Issue: 3
• DOI: https://doi.org/10.1103/PhysRevMaterials.2.034606
• Public URL: https://nottingham-repository.worktribe.com/output/922602
• Publisher URL: https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.2.034606
• Contract Date: Mar 2, 2018