A peek into the history of sapphire crystal growth

Abstract

After the chemical compositions of sapphire and ruby were unraveled in the middle of the 19 th century,

A century of sapphire crystal growth: origin of the EFG method

“…1,2,3 Verneuil aimed a downward-pointing hydrocarbon-oxygen flame at the top of a pile of aluminum oxide (Al 2 O 3 , also called alumina) powder. The flame fused some of the powder, which solidified into a small crystal.…”

Czochralski Growth of Oxides and Fluorides

“…Stepanov and EFG methods were used to make single crystal fibers, tubes, and rod-shaped sapphire [2,3]. Stepanov and EFG methods were used to make single crystal fibers, tubes, and rod-shaped sapphire [2,3].…”

Thermally-Polarized Solid-State Spin Sensor

“…Second, the ruby resonator supports a high quality-factor mode (∼ 50, 000) near the spin transition frequency [65] enabling a large single-spinphoton coupling. Third, ruby crystal growth is a mature technology, with high-purity single-crystal material available in liter-scale volumes [66,67]. Finally, ruby's anisotropy induces sufficient thermal spin polarization for high-sensitivity magnetometry at room temperature.…”