Thermal and dielectric properties of ferroelectric lead germanate single crystals doped with chromium ions (Pb5Ge3O11:Cr3+)

被引：12

作者：

Bachulska, U. ^{[1
]}

Jankowska-Sumara, J. ^{[1
]}

Majchrowski, A. ^{[2
]}

Chrunik, M. ^{[2
]}

Zasada, D. ^{[3
]}

Soszynski, A. ^{[4
]}

机构：

[1] Cracow Pedag Univ, Inst Phys, Krakow, Poland

[2] Mil Univ Technol, Inst Appl Phys, Warsaw, Poland

[3] Mil Univ Technol, Dept Adv Mat & Technol, Warsaw, Poland

[4] Univ Silesia, Inst Phys, Katowice, Poland

来源：

PHASE TRANSITIONS | 2018年 / 91卷 / 9-10期

关键词：

Ferroelectric lead germanate; phase transitions; specific heat; dielectric properties; PHASE-TRANSITION; CONDUCTIVITY;

D O I：

10.1080/01411594.2018.1507032

中图分类号：

O7 [晶体学];

学科分类号：

0702 ; 070205 ; 0703 ; 080501 ;

摘要：

Single crystals of Pb5Ge3O11 (PGO), pure and doped with Cr3+ ions, were grown by means of Czochralski and Kyropoulos method, respectively. Structural, microstructural, thermodynamic and dielectric properties were investigated in terms of Cr3+-doping. The temperature dependences of molar heat capacity in the range 120-700 K at constant pressure (c(p)) for PGO and PGO:Cr3+ (0.2%) crystals were shown. Wide lambda-shape anomalies correspond to the second-order phase transitions from ferroelectric to the paraelectric phase taking place at 453 K and 431 K for PGO and PGO:Cr3+ (0.2%), respectively. The temperature dependences of c(p) for investigated crystals were approximated by the Einstein function and near the Curie temperature the c(p) reaches the classical Dulong-Petit limited value similar to 475 J.mol(-1).K-1. Temperature dependences of dielectric permittivity measured along and perpendicular to the ferroelectric axis in the temperature range 300-550 K are investigated. These studies revealed anisotropic behavior of PGO and PGO:Cr3+ (0.2%) crystals.

引用

页码：923 / 931

页数：9

共 16 条

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