Accession Number:

AD1050180

Title:

In-situ Charge Density Imaging of Metamaterials made with Switchable Two-dimensional Electron Gas at Oxide Heterointerfaces

Descriptive Note:

[Technical Report, Final Report]

Corporate Author:

UNIVERSITY OF WISCONSIN SYSTEM

Personal Author(s):

Report Date:

2017-11-28

Pagination or Media Count:

10

Abstract:

We have designed and grown LaAlO3SrTiO3 oxide hetero-interfaces and switchable 2DEG by using pulsed laser deposition atomic within-situ reflection high-energy electron diffraction RHEED. We have also demonstrated that the inline electron holography can directly visualize the 2DEG at the both 001 and 111 LAOSTO interface. Taking an example of 2DEGs forming at LAOSTO interfaces with different crystal symmetry, we have shown that the selective orbital occupation and spatial quantum confinement of 2DEGs can be resolved with sub-nm resolution using inline electron holography. For in-situ biasing experiments in TEM, we prepared two model heterostructures of switchable 2DEG systems and performed in-situ STEM HAADF imaging of the heterostructure taken under various DC biases. The electric potential images and profiles were obtained from the reconstructed phase of transmitted electron beam after calibrating local thickness of TEM sample.

Subject Categories:

  • Miscellaneous Materials

Distribution Statement:

[A, Approved For Public Release]