Crystal growth and optical characterisation of Cr 3+-doped YAl 3(BO 3) 4

Abstract

This paper reports the high temperature top-seeded solution growth (TSSG) of large single crystals of Cr 3+-doped YAl 3(BO 3) 4 from a K 2Mo 3O 10B 2O 3 flux cooled at a rate of 2–4 K per day in the temperature range 950–1060°C, using a crystal rotation rate of 4–6 rpm. Optical absorption measurements at T = 300 K reveal broad bands associated with transitions from the 4A 2 ground state of Cr 3+ to the 4T 2 and 4T 1 excited states. The doublet R lines and their one-phonon sideband are clearly resolved at room temperature in both absorption and luminescence spectra: the splitting of the R lines demonstrates the effect of the even-parity trigonal distortions of their environment on the 4A 2 and 2E levels of the Cr 3+ ions.