Structures and pyroelectric properties for [111]‐oriented Mn‐doped rhombohedral 0.36PIN‐0.36PMN‐0.28PT crystal

Abstract

AbstractThe crystal structures, pyroelectric properties, and thermal stability of [111]‐oriented 0.5 mol% Mn‐doped 0.36Pb(In1/2Nb1/2)O3‐0.36Pb(Mg1/3Nb2/3)O3‐0.28PbTiO3 (Mn‐0.36PIN‐0.36PMN‐0.28PT) ternary single crystal were investigated. The temperature dependence of the Raman spectra and dielectric properties revealed that the crystal exhibited a rhombohedral (R) structure at room temperature, and ferroelectric R → tetragonal (T) and ferroelectric T to paraelectric cubic (C) phase transitions at 130 and 175°C respectively. The single crystal had a high remnant polarization of Pr = 38 μC cm–2 and coercive field of EC = 12 kV cm–1 at room temperature and a frequency of f = 100 Hz. The values of Pr and EC decreased with increasing temperature, exhibiting anomalies near their phase‐transition temperatures, which coincided with changes in the Raman spectra and dielectric properties. Furthermore, at 25°C and f = 100 Hz, the single crystal had high pyroelectric coefficients of p = 8.7 × 10−4 C m−2 K−1, figures of merit for the current responsivity of Fi = 3.5 × 10−10 m V−1, the voltage responsivity of Fv = 0.08 m2 C−1, and the detectivity of Fd = 30.1 × 10−5 Pa−1/2. These values were weakly dependent on temperature below 120°C. In addition, the room‐temperature pyroelectric coefficients of the ternary single crystal maintain over 83% of the original value at thermal annealing temperatures below 120°C. These outstanding pyroelectric properties, together with high thermal stability, indicate that [111]‐oriented rhombohedral Mn‐0.36PIN‐0.36PMN‐0.28PT ternary single crystal is a new potential candidate for infrared detection applications.