Investigations on structural, optical, high temperature electrical and ferroelectric properties of Neodymium doped rubidium titanyl phosphate single crystal

Abstract

Neodymium doped Rubidium Titanyl Phosphate (RTP) single crystal was grown using a high-temperature flux solution method with rubidium polyphosphate flux. Though doping does not induce changes in growth temperature, variations in material properties were observed while characterizing the grown crystal. Powder x-ray diffraction and high resolution x-ray diffraction analysis of Nd: RTP single crystal suggested the orthorhombic structure with small structural distortion and good crystalline nature. The presence of neodymium and other elements in the crystal was confirmed using EDAX analysis. The optical quality of the material was studied using optical transmittance and absorption studies. The variation in the optical band gap due to Nd doping was also analyzed. The dielectric polarization, ion hopping, activation processes, dielectric, electrical conductivity, and resistivity nature of the grown crystal were studied using impedance analysis. The properties were studied from room temperature to 850 °C, in the frequencies range from 100 Hz to 8 MHz. Then the results were compared with flux-grown pure RTP single crystals. The result exhibited superior properties on Nd doping in RTP. The low and static dielectric constant exhibited by Nd: RTP made it suitable for NLO applications. The ferroelectric nature of the Nd: RTP was analyzed from room temperature to 180 °C at an applied field of 4 kV and the PE loop was found with values of polarization and coercive field as 0.15 μC/cm2 and 1.79 kV/cm, respectively. Nd: RTP does not show any polarization decay up to 5000 frequency cycles confirmed by fatigue analysis.