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Updated: Aug 7, 2026
Piezoreflectance Spectroscopy of Optical Transitions in van der Waals Layered Crystals
Published on: May 22, 2026
Co-transition absorption property of K2ZnCl4:Co2+ crystal
Chaoyang Tu1, Fugui Yang, Jianfu Li
1Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002 Fujian, China.
Abstract:
Single-crystal K(2)ZnCl(4) doped with Co2+ has been grown successfully by use of the Czochralski technique. The absorption spectrum of the crystal was measured. The most intense line, centered at 650 nm, was associated with the transition (4)A(2)-->(4)T(1P), and a novel and important result that corporate transition (co-transition) between (4)A(2)-->(4)T(1F) and (4)A(2)-->(4)T(2) of Co2+ in the region of 1300-2400 nm was found and discussed. The mechanism that caused the phenomenon was explained by energy-level splitting theory. In the tetrahedral approximation, using the quantum and Tanaba-Sugano theories, Racah parameter B and crystal field parameter 10Dq were calculated. The optical energy gap, deduced to be 4.82 eV, was lower than that of pure K2ZnCl4.
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