The Mechanism of Electrolyte Gating on High-Tc Cuprates: The Role of Oxygen Migration and Electrostatics.
The Mechanism of Electrolyte Gating on High-Tc Cuprates: The Role of Oxygen Migration and Electrostatics.
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DOI：
10.1021/acsnano.7b03978
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发表时间：
2017-09
期刊：
影响因子：
17.1
通讯作者：
Lingchao Zhang;S. Zeng;Xinmao Yin;T. Asmara;P. Yang;K. Han;Yu Cao;Wenxiong Zhou;D. Wan;C. Tang;A. Rusydi;Ariando;T. Venkatesan
中科院分区：
文献类型：
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作者：
Lingchao Zhang;S. Zeng;Xinmao Yin;T. Asmara;P. Yang;K. Han;Yu Cao;Wenxiong Zhou;D. Wan;C. Tang;A. Rusydi;Ariando;T. Venkatesan
电解质门控广泛用于在固体表面诱导大载流子密度调制，以探索各种特性。过去的大多数工作都将电荷调制归因于静电场效应。然而，最近的一些报告认为，VO2、TiO2 和 SrTiO3 中的电解质门控效应源于场诱导的氧空位形成。这引起了关于门控机制的争议，因此揭示电解质门控的作用与材料本征性能之间的关系至关重要。在这里，我们报告了两种具有不同晶体结构的高 Tc 铜酸盐 NdBa2Cu3O7-δ (NBCO) 和 Pr2-xCexCuO4 (PCCO) 上完全不同的电解质门控机制。我们发现 NBCO 的 CuO 链中场诱导的氧空位形成起主导作用，而 PCCO 的情况主要是静电场效应。可能的原因是 NBCO 在 CuO 链中具有移动氧，而 PCCO 则没有。我们的研究有助于澄清与电解质门控机制相关的争议，从而更好地理解氧电迁移的作用，这是非常材料特定的。
Electrolyte gating is widely used to induce large carrier density modulation on solid surfaces to explore various properties. Most of past works have attributed the charge modulation to electrostatic field effect. However, some recent reports have argued that the electrolyte gating effect in VO2, TiO2, and SrTiO3 originated from field-induced oxygen vacancy formation. This gives rise to a controversy about the gating mechanism, and it is therefore vital to reveal the relationship between the role of electrolyte gating and the intrinsic properties of materials. Here, we report entirely different mechanisms of electrolyte gating on two high-Tc cuprates, NdBa2Cu3O7-δ (NBCO) and Pr2-xCexCuO4 (PCCO), with different crystal structures. We show that field-induced oxygen vacancy formation in CuO chains of NBCO plays the dominant role, while it is mainly an electrostatic field effect in the case of PCCO. The possible reason is that NBCO has mobile oxygen in CuO chains, while PCCO does not. Our study helps clarify the controversy relating to the mechanism of electrolyte gating, leading to a better understanding of the role of oxygen electro migration which is very material specific.