Raman scattering from highly-stressed anvil diamond*

Abstract

The high-frequency edge of the first-order Raman mode of diamond reflects the stress state at the culet of anvil, and is often used for the pressure calibration in diamond anvil cell (DAC) experiments. Here we point out that the high-frequency edge of the diamond Raman phonon corresponds to the Brillouin zone (BZ) center Γ point as a function of pressure. The diamond Raman pressure gauge relies on the stability of crystal lattice of diamond under high stress. Upon the diamond anvil occurs failure under the uniaxial stress (197 GPa), the loss of intensity of the first-order Raman phonon and a stress-dependent broad Raman band centered at 600 cm−1 are observed, which is associated with a strain-induced local mode corresponding to the BZ edge phonon of the L 1 transverse acoustic phonon branch.

High-pressure Raman study of osmium and rhenium up to 200 GPa and pressure dependent elastic shear modulus C 44

“…The pressure was then calibrated at room temperature by the fluorescence of ruby [36] and the high-frequency edge of diamond phonon. [37][38][39] The diameter of the Raman laser spot was ∼ 5 µm, which is smaller than the sample size (> 20 µm). This allowed to minimize the effect of the pressure gradient.…”

Investigating the thermal conductivity of materials by analyzing the temperature distribution in diamond anvils cell under high pressure

“…[1][2][3] In combination with electrical, optical, magnetic, mechanical and other methods to measure physical properties, a DAC can characterize material structure and various physical properties under high pressure. [4][5][6][7][8] Accordingly, DACs have been widely applied in diverse fields including materials science, physics and chemistry. [9][10][11][12][13][14] When a DAC is subjected to high temperatures it can simulate the conditions in the earth's interior in the laboratory, which is of great importance for investigating the thermal properties of minerals and rocks.…”