Low temperature growth of pyroelectric triglycine sulfate single crystal for passive infrared sensing

摘要

Synthesis, characterization and pyroelectric investigations on low temperature grown triglycine sulfate (TGS) single crystal is reported. Low temperature growth in this work was adopted to examine the effects on dielectric properties and pyroelectric responsivity. Developed crystal was found highly transparent on wavelengths from 223 nm to 1100 nm and free energy band was calculated to be 5.5 eV. The lattice structure of crystal was confirmed monoclinic with space group P2_1. Dielectric permittivity (ε) of the crystal measured at 27°C was found 20. The pyroelectric current (I_P) perceived in the study yield pyroelectric coefficient (ρ) of 3.34×10~(-8) C/cm~2K and consequently the ρ/ε figure of merit (Fv) to be 0.166×10~(-8) C/cm~2K. An additive enhancement in the pyroelectric figure of merit (Fv) was calculated due to the lower value of dielectric permittivity.