Sapphire Raman Spectrum

Alumina (Al₂O₃) is an important ceramic material utilized extensively in the industrial fields of electronics, optics, and mechanical engineering. The most thermodynamically stable form of alumina is Sapphire α-Al₂O₃ (or corundum). It has an extremely high melting point of 2053°C, superior resistance to chemicals, exceptional durability, and great compressive strength — all of which make sapphire an excellent candidate for applications in sensing ultra-high optical temperature. The second hardest transparent crystalline material, next to diamond, sapphire exhibits broadband optical transmittance, large index of refraction (η~1.77), and high laser damage threshold. It is also used widely in nuclear applications due to its considerable resistance to radiation. Sapphire coating can be incorporated in various components with a high thermal rating as a means of effective temperature regulation in harsh-environment applications.

Raman spectroscopy of Al₂O₃

Al₂O₃ Raman spectroscopy is a powerful tool of nondestructive material characterization, which has been used to study different crystalline structures. Thus, Sapphire Raman spectra can provide much insight into the phonon vibration patterns to facilitate structural analysis.