Electrolyte gate controlled metal-insulator transitions of the CaZrO3/SrTiO3 heterointerface

Wei Niu, Yongda Chen, Yulin Gan, Yu Zhang, Xiaoqian Zhang, Xiao Yuan, Zhi Cao, Wenqing Liu, Yongbing Xu, Rong Zhang, Nini Pryds, Yunzhong Chen, Yong Pu, Xuefeng Wang*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Two-dimensional electron gas (2DEG) at a complex oxide interface shows an extraordinary spectrum of intriguing phenomena and functionality. Another oxide 2DEG was recently created via strain-induced polarization at an otherwise nonpolar perovskite-type interface of CaZrO3/SrTiO3 (CZO/STO). Herein, we report an effective way to tune the CZO/STO interface via ionic liquid (IL) electrolyte gating. An unexpected metal-insulator transition of the interfacial 2DEG occurs readily with the immersion of the sample in an IL even before the gate voltage is applied. This suggests the presence of intrinsic polarization of CZO, which could act as a negative bias. The carrier density is found to be suppressed and shows a temperature-independent behavior after electrolyte gating which also resulted in higher electron mobility. These results suggest that the oxygen vacancies are annihilated via oxygen electromigration to the interface induced by electrolyte gating. The effective tunability by IL gating shed more light on the mechanism of electrolyte gating on the buried heterointerface.
Original languageEnglish
Article number061601
JournalApplied Physics Letters
Volume115
Issue number6
Number of pages5
ISSN0003-6951
DOIs
Publication statusPublished - 2019

Cite this

Niu, Wei ; Chen, Yongda ; Gan, Yulin ; Zhang, Yu ; Zhang, Xiaoqian ; Yuan, Xiao ; Cao, Zhi ; Liu, Wenqing ; Xu, Yongbing ; Zhang, Rong ; Pryds, Nini ; Chen, Yunzhong ; Pu, Yong ; Wang, Xuefeng. / Electrolyte gate controlled metal-insulator transitions of the CaZrO3/SrTiO3 heterointerface. In: Applied Physics Letters. 2019 ; Vol. 115, No. 6.
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title = "Electrolyte gate controlled metal-insulator transitions of the CaZrO3/SrTiO3 heterointerface",
abstract = "Two-dimensional electron gas (2DEG) at a complex oxide interface shows an extraordinary spectrum of intriguing phenomena and functionality. Another oxide 2DEG was recently created via strain-induced polarization at an otherwise nonpolar perovskite-type interface of CaZrO3/SrTiO3 (CZO/STO). Herein, we report an effective way to tune the CZO/STO interface via ionic liquid (IL) electrolyte gating. An unexpected metal-insulator transition of the interfacial 2DEG occurs readily with the immersion of the sample in an IL even before the gate voltage is applied. This suggests the presence of intrinsic polarization of CZO, which could act as a negative bias. The carrier density is found to be suppressed and shows a temperature-independent behavior after electrolyte gating which also resulted in higher electron mobility. These results suggest that the oxygen vacancies are annihilated via oxygen electromigration to the interface induced by electrolyte gating. The effective tunability by IL gating shed more light on the mechanism of electrolyte gating on the buried heterointerface.",
author = "Wei Niu and Yongda Chen and Yulin Gan and Yu Zhang and Xiaoqian Zhang and Xiao Yuan and Zhi Cao and Wenqing Liu and Yongbing Xu and Rong Zhang and Nini Pryds and Yunzhong Chen and Yong Pu and Xuefeng Wang",
year = "2019",
doi = "10.1063/1.5108813",
language = "English",
volume = "115",
journal = "Applied Physics Letters",
issn = "0003-6951",
publisher = "American Institute of Physics",
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Niu, W, Chen, Y, Gan, Y, Zhang, Y, Zhang, X, Yuan, X, Cao, Z, Liu, W, Xu, Y, Zhang, R, Pryds, N, Chen, Y, Pu, Y & Wang, X 2019, 'Electrolyte gate controlled metal-insulator transitions of the CaZrO3/SrTiO3 heterointerface', Applied Physics Letters, vol. 115, no. 6, 061601. https://doi.org/10.1063/1.5108813

Electrolyte gate controlled metal-insulator transitions of the CaZrO3/SrTiO3 heterointerface. / Niu, Wei; Chen, Yongda; Gan, Yulin; Zhang, Yu; Zhang, Xiaoqian; Yuan, Xiao; Cao, Zhi; Liu, Wenqing; Xu, Yongbing; Zhang, Rong; Pryds, Nini; Chen, Yunzhong; Pu, Yong; Wang, Xuefeng.

In: Applied Physics Letters, Vol. 115, No. 6, 061601, 2019.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Electrolyte gate controlled metal-insulator transitions of the CaZrO3/SrTiO3 heterointerface

AU - Niu, Wei

AU - Chen, Yongda

AU - Gan, Yulin

AU - Zhang, Yu

AU - Zhang, Xiaoqian

AU - Yuan, Xiao

AU - Cao, Zhi

AU - Liu, Wenqing

AU - Xu, Yongbing

AU - Zhang, Rong

AU - Pryds, Nini

AU - Chen, Yunzhong

AU - Pu, Yong

AU - Wang, Xuefeng

PY - 2019

Y1 - 2019

N2 - Two-dimensional electron gas (2DEG) at a complex oxide interface shows an extraordinary spectrum of intriguing phenomena and functionality. Another oxide 2DEG was recently created via strain-induced polarization at an otherwise nonpolar perovskite-type interface of CaZrO3/SrTiO3 (CZO/STO). Herein, we report an effective way to tune the CZO/STO interface via ionic liquid (IL) electrolyte gating. An unexpected metal-insulator transition of the interfacial 2DEG occurs readily with the immersion of the sample in an IL even before the gate voltage is applied. This suggests the presence of intrinsic polarization of CZO, which could act as a negative bias. The carrier density is found to be suppressed and shows a temperature-independent behavior after electrolyte gating which also resulted in higher electron mobility. These results suggest that the oxygen vacancies are annihilated via oxygen electromigration to the interface induced by electrolyte gating. The effective tunability by IL gating shed more light on the mechanism of electrolyte gating on the buried heterointerface.

AB - Two-dimensional electron gas (2DEG) at a complex oxide interface shows an extraordinary spectrum of intriguing phenomena and functionality. Another oxide 2DEG was recently created via strain-induced polarization at an otherwise nonpolar perovskite-type interface of CaZrO3/SrTiO3 (CZO/STO). Herein, we report an effective way to tune the CZO/STO interface via ionic liquid (IL) electrolyte gating. An unexpected metal-insulator transition of the interfacial 2DEG occurs readily with the immersion of the sample in an IL even before the gate voltage is applied. This suggests the presence of intrinsic polarization of CZO, which could act as a negative bias. The carrier density is found to be suppressed and shows a temperature-independent behavior after electrolyte gating which also resulted in higher electron mobility. These results suggest that the oxygen vacancies are annihilated via oxygen electromigration to the interface induced by electrolyte gating. The effective tunability by IL gating shed more light on the mechanism of electrolyte gating on the buried heterointerface.

U2 - 10.1063/1.5108813

DO - 10.1063/1.5108813

M3 - Journal article

VL - 115

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 0003-6951

IS - 6

M1 - 061601

ER -