中文摘要：

以（1-x）Pb（Mg1/3Nb2/3）O3-xPbTiO3{PMNT[（1-x）/x]}为代表的大尺寸、高质量弛豫铁电单晶具有非常高的热释电系数、探测优值和较低的热扩散系数,其综合热释电性能远优于传统的热释电材料。概述了PMNT[（1-x）/x]单晶、掺锰PMNT（74/26）单晶和0.42Pb（In1/2Nb1/2）O3-0.3Pb（Mg1/3Nb2/3）O3-0.28PbTiO3[PIMNT（42/30/28）]单晶的介电性能、铁电性能和热释电性能。掺杂后PMNT（74/26）单晶的介电损耗降低到0.000 5,探测优值提高到40.2×10^-5 Pa^-1/2,是目前所有三方四方相变温度（TRT）高于90°C的本征热释电材料中最高的。高居里温度PIMNT（42/30/28）单晶的TRT达到152°C,且具有较高的探测优值（10.2×10^-5 Pa^-1/2）,将在更宽温度范围内得到广泛的应用。制作了基于掺锰PMNT（74/26）单晶的单元探头,其比探测率D＊达到1.07×10^9 cmHz1/2W-1,是目前商用LiTaO3探测器的两倍,器件性能满足实用要求。

英文摘要：

The large-size,high-quality relaxor-based ferroelectric single crystals represented by（1-x）Pb（Mg1/3Nb2/3） O3-xPbTiO3 {PMNT [（1-x）/x]} perform very high pyroelectric coefficient,detectivity figures of merit and relatively low thermal diffusivity,which makes its comprehensive pyroelectric properties far superior to the traditional pyroelectric materials.The dielectric,ferroelectric and pyroelectric properties of the PMNT [（1-x）/x],Mn-doped PMNT（74/26） and 0.42Pb（In1/2Nb1/2）O3-0.3Pb（Mg1/3Nb2/3）O3-0.28PbTiO3 [PIMNT（42/30/28）] single crystals were overviewed.The dielectric loss of Mn-doped PMNT（74/26） crystals was declined to 0.000 5,and the detectivity figures of merit was enhanced to 40.2×10^-5 Pa^-1/2,which was the highest value so far reported among intrinsic pyroelectric materials with TRT higher than 90 °C.High-Curie-temperature PIMNT（42/30/28） crystals with TRT of 152 ° C,employed relatively high detectivity figures of merit（10.2 ×10^-5 Pa^-1/2）,would be widely used in a wider temperature range.The specific detectivity of infrared detector based on Mn-doped PMNT（74/26） crystals was 1.07×10^9 cmHz1/2W-1,and approximately doubled that of commercial LiTaO3 crystals-based,which made it promising candidates for infrared detectors applications.