Novel electrode layout for relaxor single crystal pyroelectric detectors with enhanced responsivity and specific detectivity

• Distributed electrode structure of sensitive element was designed for PMNT based pyroelectric infrared detector.
• Different electrode distances have been investigated for this structure.
• Under the optimal electrode distance of 0.5 mm, the figure of merit for detectivity is up to 39.9 × 10−5 Pa−1/2.
• Three forms of figure of merit for detectivity were derived based on the different mechanisms.
• The responsivity and specific detectivity of the proposed structure are 3.6 and 1.4 times higher than that of the conventional faced electrode structure.

A distributed electrode structure of sensitive element based on Mn-doped Pb(Mg1/3Nb2/3)O3-0.29PbTiO3 single crystals for high-end pyroelectric infrared detectors has been proposed, demonstrating a notably superior pyroelectric response. Under the optimal electrode distance of 0.5 mm, the figure of merit for detectivity is up to 39.9 × 10−5 Pa−1/2. An ultrahigh responsivity of 864 V/W and specific detectivity of 1.49 × 109 cm Hz1/2/W at 10 Hz are observed, approximately 3.6 and 1.4 times higher, respectively, than that of the conventional faced electrode structure. The enhanced responsivity and specific detectivity of the distributed electrode structure will make PMNT based detectors with voltage mode promising in practical use of sensors.