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arXiv · 2008.04225

Effect of isotope disorder on the Raman spectra of cubic boron arsenide

Akash Rai·Sheng Li·Hanlin Wu·Bing Lv·David G. Cahill
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Abstract

Boron arsenide (c-BAs) is at the forefront of research on ultrahigh thermal conductivity materials. We present a Raman scattering study of isotopically tailored cubic boron arsenide single crystals for 11 isotopic compositions spanning the range from nearly pure c-$^{10}$BAs to nearly pure c-$^{11}$BAs. Our results provide insights on the effects of strong mass disorder on optical phonons and the appearance of two-mode behavior in the Raman spectra of mixed crystals. Strong isotope disorder also relaxes the one-phonon Raman selection rules, resulting in disorder-activated Raman scattering by acoustic phonons.

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Akash Rai, Sheng Li, Hanlin Wu, Bing Lv, David G. Cahill. 2020-08-10. Effect of isotope disorder on the Raman spectra of cubic boron arsenide. https://doi.org/10.1103/physrevmaterials.5.013603

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