A位La掺杂的单晶化合物Sr2IrO4电输运特性

doi:10.15541/jim20170568

无机材料学报 ›› 2018, Vol. 33 ›› Issue (9): 1001-1005.DOI: 10.15541/jim20170568

A位La掺杂的单晶化合物Sr₂IrO₄电输运特性

段天赐^{1, 2}, 王好文³, 王伟³, 裴玲^{1, 2}, 胡妮^{1, 2}

1. 湖北工业大学太阳能高效利用湖北省协同创新中心, 武汉 430068;
2. 湖北工业大学理学院, 武汉 430068;
3. 华中科技大学物理学院, 武汉 430074

收稿日期:2017-11-27 修回日期:2018-03-23 出版日期:2018-09-20 网络出版日期:2018-08-14
作者简介:段天赐(1991-), 男, 硕士研究生. E-mail: 237484470@qq.com
基金资助:
国家自然科学基金(11374112, 11304091, 11604089)

Electrical Transport Property of A-site La Doped of Sr₂IrO₄

DUAN Tian-Ci^{1, 2}, WANG Hao-Wen³, WANG Wei³, PEI Ling^{1, 2}, HU Ni^{1, 2}

1. Hubei Collaborative Innovation Center for High-efficient Utilization of Solar Energy, Hubei University of Technology, Wuhan 430068, China;
2. School of Science, Hubei University of Technology, Wuhan 430068, China;
3. School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China

Received:2017-11-27 Revised:2018-03-23 Published:2018-09-20 Online:2018-08-14
About author:DUAN Tian-Ci. E-mail: 237484470@qq.com
Supported by:
National Natural Science Foundation of China (11374112, 11304091, 11604089)

摘要/Abstract

摘要：

5 d强自旋轨道耦合氧化物Sr₂IrO₄中的电输运物理是该领域存在争议的一个科学问题。本研究应用flux法成功制备(Sr_1-_xLa_x)₂IrO₄(x=0, 0.01, 0.02, 0.03, 0.05)等系列单晶样品, 并通过综合物性测量仪对样品电输运特性进行表征。研究表明: 随着La掺杂浓度的增加, 样品体系电阻率显著下降, 并在x≥0.03时出现金属性(dρ_ab/dT>0)。通过对样品电阻率的一系列拟合发现, 未掺杂的Sr₂IrO₄单晶样品在高温部分(T>140 K)和较低温区(40 K<T<80 K)导电机制符合三维变程跳跃模型, 中温部分(80 K<T<140 K)导电机制则符合热激发机制; 而掺杂样品仅在较低温部分(T<90 K)呈现出明显的变程跳跃电导, 并且样品中的激活能随掺杂量增加而减小。通过变程跳跃电导模型拟合发现, 掺杂样品中的局域化长度明显大于Ir-O键长, 可能是源于系统中载流子产生的退局域化效应。

关键词: Sr₂IrO₄ Mott绝缘体, 电输运, 热激活, 三维变程跃迁

Abstract:

The physics of electric transport in iridate Sr₂IrO₄ has been a long term controversial issue in the field of 5d oxides. A series of single crystal samples (Sr_1-_xLa_x)₂IrO₄ were prepared by flux method, and their electrical transport properties were investigated. The results reveal that the sample shows metallic transport at x≥0.03. A close examination of the transport data reveals drastic modulation for the conduction mechanism upon La-doping. For the non-doped sample, three-dimensional Mott variable range hopping conduction is respectively identified at T>140 K and 40 K<T<80 K, and thermal activation conduction is revealed at 80 K<T<140 K. For the doped sample, the Mott variable range hopping conduction is only found at T<90 K, and the activation energy is revealed to decrease with the La-doping content increasing. In addition, the localization length of the doped samples is found to be much larger than the Ir-O bond length, which may due to delocalization effect of the carriers in the systems.

Key words: Sr₂IrO₄ Mott insulator, electric transport, thermal activation, 3D variable range hopping

中图分类号:

O513

段天赐, 王好文, 王伟, 裴玲, 胡妮. A位La掺杂的单晶化合物Sr₂IrO₄电输运特性[J]. 无机材料学报, 2018, 33(9): 1001-1005.

DUAN Tian-Ci, WANG Hao-Wen, WANG Wei, PEI Ling, HU Ni. Electrical Transport Property of A-site La Doped of Sr₂IrO₄[J]. Journal of Inorganic Materials, 2018, 33(9): 1001-1005.

图/表 4

图1 (Sr1-xLax)2IrO4(x=0, 0.01, 0.02, 0.03, 0.05)样品的XRD图谱

Fig. 1 XRD patterns of (Sr1-xLax)2IrO4(x=0 ,0.01, 0.02, 0.03, 0.05)

图2 (Sr1-xLax)2IrO4(x=0, 0.01, 0.02, 0.03, 0.05)的ρab vs T曲线

Fig. 2 ρab vs T plots of (Sr1-xLax)2IrO4(x=0, 0.01, 0.02, 0.03, 0.05)From top to bottom: x=0, 0.01, 0.02, 0.03, 0.05, respectively Inset shows detail of the (Sr1-xLax)2IrO4(x=0.03, 0.05)

图3 (Sr1-xLax)2IrO4(x=0, 0.01, 0.02, 0.03, 0.05)的lnρab vs T-1曲线和lnρab vs T-1/4曲线以及对应线性拟合曲线

Fig. 3 lnρab vs T-1 and lnρab vs T-1/4 plot of (Sr1-xLax)2IrO4(x=0, 0.01, 0.02, 0.03, 0.05) Upper level from left to right (a)-(e); lower lever from left to right (a1)~(e1)Straight lines (a)~(e) are fitting of data following Eq. (1), straight lines (a1)-(e1) are fitting of data following Eq.(2), with vertical arrows mark for the corresponding temperature

表1 热激活模型和3D-VRH模型拟合参数

Table 1 Fitting parameters to the thermal activation model and 3D Mott variable range hopping model for single crystal (Sr1-xLax)2IrO4 (x=0, 0.01, 0.02, 0.03, 0.05)

x	Δ/meV	T_M/(×10⁴, K)	(R_M/a)/K^-1/4	a/nm	E_M/meV
0	84.4	?39	9.4 T^1/4	0.320	0.54 T^3/4
0	84.4	6561	33.8/T^1/4	0.058	1.94 T^3/4
0.01	6.4	?0.0016	0.75 T^1/4	9.300	0.04 T^3/4
0.01	6.4	2.8	4.8/T^1/4	0.770	0.28 T^3/4
0.02	6.2	0.45	3.1/T^1/4	1.430	0.18 T^3/4
0.03	1.5	0.0028	0.9/T^1/4	7.790	0.05 T^3/4
0.05	2.1	0.0092	1.2/T^1/4	5.310	0.07 T^3/4

参考文献 24

[1]	CAO G, QI T F, LI L, et al. Evolution of magnetism in single- crystal honeycomb iridates. Phys. Rev. B, 2013, 88(22): 220414-1-8.
[2]	KIM B J, OHSUMI H, KOMESU T,et al. Phase-sensitive observation of a spin-orbital Mott state in Sr2IrO4. Science, 2009, 323(5919): 1329-1332.
[3]	WANG F, SENTHIL T.Twisted Hubbard model for Sr2IrO4: magnetism and possible high temperature superconductivity.Phys. Rev. Lett., 2011, 106(13): 186-197.
[4]	WATANABE H, SHIRAKAWA T, YUNOKI S. Monte Carlo study of an unconventional superconducting phase in iridium oxide Jeff=1/2 Mott insulators induced by carrier doping. Phys. Rev. Lett., 2013, 110(2): 027002-1-5.
[5]	MENG Z Y, KIM Y B, KEE H Y. Odd-parity triplet superconducting phase in multi-orbital materials with a strong spin-orbit coupling: application to doped Sr2IrO4. Phys. Rev. Lett., 2014, 113(17): 177003-1-5.
[6]	LU C L, QUINDEAU A, DENIZ H, et al. Crossover of conduction mechanism in Sr2IrO4 epitaxial thin films. Appl. Phys. Lett., 2014, 105(8): 082407-1-5.
[7]	YAN Y J, REN M Q, XU H C, et al. Electron-doped Sr2IrO4: an analogue of hole-doped cuprate superconductors demonstrated by scanning tunneling microscopy. Phys. Rev. X, 2015, 5(4): 041018- 1-7.
[8]	CAO G, XIN Y, ALEXANDER C S, et al. Anomalous magnetic and transport behavior in the magnetic insulator Sr3Ir2O7. Phys. Rev. B, 2002, 66(21): 214412-1-7.
[9]	FUJIOKA J, OKAWA T, YAMAMOTO A, et al. Correlated Dirac semi-metallic state with unusual positive magnetoresistance in strain-free perovskite SrIrO3. Phys. Rev. B, 2017, 95(12): 121102-1-5.
[10]	LU C L, DONG S, QUINDEAU A, et al. Dual gate control of bulk transport Dual gate control of bulk transport and magnetism in the spin-orbit insulator Sr2IrO4. Phys. Rev. B, 2015, 91(10): 104401-1-9.
[11]	KITTAKA S, TANIGUCHI H, YONEZAWA S, et al. Higher-Tc superconducting phase in Sr2RuO4 induced by uniaxial pressure. Phys. Rev. B, 2010, 81(18): 180510-1-4.
[12]	CAI X, YING Y A, STALEY N E, et al. Unconventional quantum oscillations in mesoscopic rings of spin-triplet superconductor Sr2RuO4. Phys. Rev. B, 2013, 87(8): 081104-1-5.
[13]	GE M, TAN S, SHAO J, et al. Interaction between 3d-, 4d-and 5d-electron in Sr2Ir1-x(Ru,Ti)xO4. J. Magn. Magn. Mater., 2014, 369: 223-227.
[14]	KIM B J, JIN H, MOON S J, et al. Novel Jeff =1/2 Mott state induced by relativistic spin-orbit coupling in Sr2IrO4. Phys. Rev. Lett., 2008, 101(7): 076402-1-4.
[15]	CAO G, BOLIVAR J, MCCALL S,et al. Weak ferromagnetism, metal-to-nonmetal transition, and negative differential resistivity in single-crystal Sr2IrO4. Phys. Rev. B, 1998, 57(18): R11039-R11042.
[16]	BAHR S, ALFONSOV A, JACKELI G, et al. Low-energy magnetic excitations in the spin-orbital Mott insulator Sr2IrO4. Phys. Rev. B, 2014, 89(18): 180401-1-5.
[17]	CHEN X, HOGAN T, WALKUP D, et al. Influence of electron doping on the ground state of Influence of electron doping on the ground state of (Sr1-xLax)2IrO4. Phys. Rev. B, 2015, 92(7): 075125-1-11.
[18]	GE M, QI T F, KORNETA O B,et al. Lattice-driven magnetoresistivity and metal-insulator transition in single-layered iridates. Phys. Rev. B, 2011, 84(10): 3382-3391.
[19]	QI T F, KORNETA O B, LI L, et al. Spin-orbit tuned metal-insulator transitions in single-crystal Sr2Ir1-xRhxO4 (0≤x≤1). Phys. Rev. B, 2012, 86(12): 125105-1-6.
[20]	YUAN S J, ASWARTHAM S, TERZIC J, et al. From Jeff=1/2 insulator to p-wave superconductor in single-crystal Sr2Ir1-xRuxO4 (0 ≤ x ≤ 1). Phys. Rev B, 2015, 92(24): 245103-1-6.
[21]	CHENG L, WANG L L, PU S J,et al. Structure and electric transport properties of the spin ladder compound Sr14(Cu0.97M0.03)24O41, 2010, 59(2): 1155-1162.
[22]	KLEIN Y, TERASAKI I.Insight on the electronic state of Sr2IrO4 revealed by cationic substitutions.J. Phys.: Condens. Matter., 2008, 20(29): 2123-2131.
[23]	MOTT N F.Conduction in glasses containing transition metal ions.J. Non-Cryst. Solids, 1968, 1(1): 1-17.
[24]	ROSENBAUM R.Crossover from Mott to Efros-Shklovskii variable- range-hopping conductivity in In xOy films. Phys. Rev. B, 1991, 44(8): 3599-3603.

A位La掺杂的单晶化合物Sr₂IrO₄电输运特性

Electrical Transport Property of A-site La Doped of Sr₂IrO₄

RichHTML

PDF (PC)

可视化

摘要/Abstract

引用本文

使用本文

图/表 4

参考文献 24

相关文章 8

编辑推荐

Metrics

本文评价

[1]	张爱梅, 朱佳佳, 方天诚, 潘茜茜. Al³⁺掺杂对La_0.8Sr_0.2Mn_1-_xAl_xO₃电输运性能的影响[J]. 无机材料学报, 2023, 38(2): 148-154.
[2]	王慧, 张淑娟, 陈亭伟, 张传林, 罗豪甦, 郑仁奎. PdSe₂半导体薄膜的真空硒化法制备研究[J]. 无机材料学报, 2021, 36(7): 779-784.
[3]	李鹏, 聂晓蕾, 田烨, 方文兵, 魏平, 朱婉婷, 孙志刚, 张清杰, 赵文俞. Bi_0.5Sb_1.5Te₃/环氧树脂柔性复合热电厚膜的制备及其面内制冷性能[J]. 无机材料学报, 2019, 34(6): 679-684.
[4]	赵伟康, 张忻, 冯琦, 赵吉平, 刘洪亮, 李凡, 肖怡新, 刘燕琴, 张久兴. Sr掺杂对12CaO·7Al₂O₃电子化合物电输运及发射性能的影响[J]. 无机材料学报, 2019, 34(5): 521-528.
[5]	骆军, 何世洋, 李志立, 李永博, 王风, 张继业. 热电材料高通量实验制备与表征方法[J]. 无机材料学报, 2019, 34(3): 247-259.
[6]	朱明康, 董显林, 陈莹, 丁国际, 王根水. 残余应力对SrRuO₃薄膜磁学及电输运性能的影响[J]. 无机材料学报, 2017, 32(1): 75-80.
[7]	张媛媛, 唐晓东, 陈莹, 王根水, 董显林. La_0.7Ca_0.3-_xSr_xMnO₃薄膜的电输运特性研究[J]. 无机材料学报, 2016, 31(3): 274-278.
[8]	别业广, 胡妮, 刘丰铭, 段天赐, 裴玲, 邓罡. La_0.4Ca_0.6Mn_0.98Ru_0.02O₃中的电致电阻效应研究[J]. 无机材料学报, 2016, 31(11): 1255-1257.