Conductions through head-to-head and tail-to-tail domain walls in LiNbO3 nanodevices
Conductions through head-to-head and tail-to-tail domain walls in LiNbO3 nanodevices
复制标题
LiNbO3 纳米器件中通过头对头和尾对尾畴壁的传导
DOI：
10.1016/j.jallcom.2021.159837
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发表时间：
2021-04-17
影响因子：
6.2
通讯作者：
Jiang, Anquan
中科院分区：
文献类型：
--
作者：
Chai, Xiaojie;Lian, Jianwei;Jiang, Anquan
在绝缘铁电基体中的导电畴壁对于开发具有大输出功率的下一代多功能纳米器件是有趣的。然而，导电是多样化的头对头（H-H），中性（N），和尾到尾（T-T）域壁（DW）与有争议的导电机制。一般认为，带电的DW比中性DW更导电。然而，由于高去极化能量，带电壁是不稳定的。在这里，我们稳定的H-H DWs，NDW和T-T DWs内的铌酸锂晶体管通过控制电荷注入在施加漏极-栅极，漏极-源极和栅极-源极电压下的畴边界电荷的补偿。通过局部180度畴反转以不同的倾斜角度产生壁，在5 mol.%的表面上制备了不同尺寸的晶体管。MgO掺杂的LiNbO 3单晶的单畴图案。NDW是带正电的，这是由于小的倾斜角（类似于1度）和带电偶极子的局部侧向弯曲行为，其电导率比跨T-T DW的电导率高三个数量级，但比跨H-H DW的电导率低一个数量级。壁电流的电压依赖性可以根据空间电荷限制电流方程进行拟合，在某些特定的电压范围内，指数系数在2.1和3.7之间变化，这意味着在不同的倾斜壁角对降低的施加电压的不连续的畴回缩影响壁电流。这一发现为通过畴重构改善畴壁导电提供了基础物理，并拓宽了畴壁在未来纳米器件中的应用。(c)2021爱思唯尔有限公司版权所有。
Conducting domain walls in an insulating ferroelectric matrix are interesting for the development of next generation multifunctional nanodevices with large output powers. However, electrical conductions are diversified among head-to-head (H-H), neutral (N), and tail-to-tail (T-T) domain walls (DWs) with disputable conduction mechanisms. It is generally accepted that the charged DWs are more electrically conductive than the neutral DWs. However, the charged walls are unstable due to high depolarization energies. Here, we stabilized the H-H DWs, NDWs and T-T DWs within a LiNbO3 transistor by controlling charge injection in compensation of the domain boundary charge under applied drain-gate, drain-source and gate-source voltages. The walls were created through the local 180 degrees domain reversals in different inclined angles, and the transistors in different sizes were fabricated at the surfaces of 5 mol.% MgO-doped LiNbO3 single crystals in monodomain patterns. The NDWs are positively charged due to small inclination angles (similar to 1 degrees) and local sideways meandering behavior of the charged dipoles with electrical conduction that is three orders of magnitude higher than that across the T-T DWs but is one order of magnitude lower than that across the H-H DWs. Voltage dependences of wall currents can be fitted according to the space-charge-limited current equation with an exponential coefficient varying between 2.1 and 3.7 in some specific voltage ranges, implying discontinuous domain retraction in different inclined wall angles against the reduced applied voltage to affect the wall current. This finding provides the fundamental physics to improve domain wall conduction via domain reconstruction and broadens the domain wall application in future nano-devices. (c) 2021 Elsevier B.V. All rights reserved.