Advantages and limitation of Mn doped PIN–PMN–PT single crystals in pyroelectric detectors

The outstanding pyroelectric coefficient p of Mn:PIN–PMN–PT makes it an interesting material for application in pyroelectric infrared detectors. In comparison to the standard material lithium tantalate (LT), the pyroelectric coefficient is higher by a factor of 4. On the other hand, the dielectric permittivity εp is about one order of magnitude higher compared to LT. Due to the higher permittivity, the resulting Figures of Merit (FOM) show the highest performance advantages for Mn:PIN–PMN–PT in the lower frequency range between 1 Hz and 10 Hz. The FOM FR of 278 · 10−12 m/V exceeds by half an order of magnitude the value of LT of 54 · 10−12 m/V. Outstanding specific detectivities around D* ≈ 1.0 · 109 cm√Hz/W at low frequencies even at a relatively low chip size were achieved. The detector fabrication needs adaption of the processes to avoid depolarization due to high temperature impact or mechanical stress.