Quantum Confinement in Oxide Heterostructures: Room-Temperature Intersubband Absorption in SrTiO3/LaAlO3 Multiple Quantum Wells

被引：15

作者：

Ortmann, J. Elliott ^{[1
]}

Nookala, Nishant ^{[2
,3
]}

He, Qian ^{[4
]}

Gao, Lingyuan ^{[1
]}

Lin, Chungwei ^{[1
,5
]}

Posadas, Agham B. ^{[1
]}

Borisevich, Albina Y. ^{[4
]}

Belkin, Mikhail A. ^{[2
,3
]}

Demkov, Alexander A. ^{[1
]}

机构：

[1] Univ Texas Austin, Dept Phys, Austin, TX 78712 USA

[2] Univ Texas Austin, Dept Elect & Comp Engn, Austin, TX 78712 USA

[3] Univ Texas Austin, Microelect Res Ctr, Austin, TX 78758 USA

[4] Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA

[5] Mitsubishi Elect Res Labs, Cambridge, MA 02139 USA

来源：

ACS NANO | 2018年 / 12卷 / 08期

基金：

美国国家科学基金会;

关键词：

transition metal oxides; intersubband transitions; quantum wells; oxide-oxide interface; heterostructure; thin films; OPTICAL-PROPERTIES; ELECTRON-GAS; INTERFACES; SUPERLATTICES; SRTIO3; SUPERCONDUCTIVITY; PHOTOLUMINESCENCE; FERROMAGNETISM; COEXISTENCE; MODE;

D O I：

10.1021/acsnano.8b01293

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The Si-compatibility of perovskite heterostructures offers the intriguing possibility of producing oxide-based quantum well (QW) optoelectronic devices for use in Si photonics. While the SrTiO3/LaAlO3 (STO/LAO) system has been studied extensively in the hopes of using the interfacial two-dimensional electron gas in Si-integrated electronics, the potential to exploit its giant 2.4 eV conduction band offset in oxide-based QW optoelectronic devices has so far been largely ignored. Here, we demonstrate room-temperature intersubband absorption in STO/LAO QW heterostructures at energies on the order of hundreds of meV, including at energies approaching the critically important telecom wavelength of 1.55 mu m. We demonstrate the ability to control the absorption energy by changing the width of the STO well layers by a single unit cell and present theory showing good agreement with experiment. A detailed structural and chemical analysis of the samples via scanning transmission electron microscopy and electron energy loss spectroscopy is presented. This work represents an important proof-of-concept for the use of transition metal oxide QWs in Si-compatible optoelectronic devices.

引用

页码：7682 / 7689

页数：8