Evolution of optical properties of chromium spinels CdCr$_2$O$_4$, HgCr$_2$S$_4$, and ZnCr$_2$Se$_4$ under high pressure

K. Rabia; L. Baldassarre; J. Deisenhofer; V. Tsurkan; C. A. Kuntscher

doi:10.1103/PhysRevB.89.125107

paper

Evolution of optical properties of chromium spinels CdCr $_{2}$ O $_{4}$ , HgCr $_{2}$ S $_{4}$ , and ZnCr $_{2}$ Se $_{4}$ under high pressure

arXiv:1402.5852 · doi:10.1103/PhysRevB.89.125107

Abstract

We report pressure-dependent reflection and transmission measurements on ZnCr $_{2}$ Se $_{4}$ , HgCr $_{2}$ S $_{4}$ , and CdCr $_{2}$ O $_{4}$ single crystals at room temperature over a broad spectral range 200-24000 cm $^{- 1}$ . The pressure dependence of the phonon modes and the high-frequency electronic excitations indicates that all three compounds undergo a pressure-induced structural phase transition with the critical pressure 15 GPa, 12 GPa, and 10 GPa for CdCr $_{2}$ O $_{4}$ , HgCr $_{2}$ S $_{4}$ , and ZnCr $_{2}$ Se $_{4}$ , respectively. The eigenfrequencies of the electronic transitions are very close to the expected values for chromium crystal-field transitions. In the case of the chalcogenides pressure induces a red shift of the electronic excitation which indicates a strong hybridization of the Cr d-bands with the chalcogenide bands.

Accepted for publication in Phys. Rev. B

Evolution of optical properties of chromium spinels CdCr2​O4​, HgCr2​S4​, and ZnCr2​Se4​ under high pressure

Abstract

References in corpus (8)

Evolution of optical properties of chromium spinels CdCr $_{2}$ O $_{4}$ , HgCr $_{2}$ S $_{4}$ , and ZnCr $_{2}$ Se $_{4}$ under high pressure