Growth and characterization of a highly homogeneous Er0.12Y0.88COB crystal for nonlinear optical applications

Abstract

Yttrium calcium oxyborate (YCOB) crystals are excellent candidate materials for nonlinear optical (NLO) applications. In this work, a two-inch b-axis Er_0.12Y_0.88COB crystal was grown successfully by the Czochralski method. Samples used for performance evaluation were cut from the top, middle and bottom parts of the as-grown crystal. Rocking curves, inductively coupled plasma-optical emission spectroscopy (ICP-OES), energy dispersive spectrometry (EDS), transmission spectra and an interferometer were used to determine the crystalline quality, composition and optical homogeneity of the Er:YCOB crystal. The full width at half maximum (FWHM) value of the rocking curve of Er:YCOB is about 30′′. The Er³⁺ and Y³⁺ distribution and UV cut-off value revealed the high compositional homogeneity of the Er:YCOB crystal. The specific heat and thermal conductivity of Er:YCOB were studied and are slightly smaller than that of pure YCOB. In addition, an absorption peak at around 1537 nm makes Er:YCOB a potential crystal for quasi-parametric chirped-pulse amplification (QPCPA) applications in the mid-infrared band.