Issue 35, 2016

An AlAs/germanene heterostructure with tunable electronic and optical properties via external electric field and strain

Abstract

By means of comprehensive first-principles calculations, we investigate the stability, electronic and optical properties of an AlAs/germanene heterostructure. In particular, electric field and strain are used to tailor its electronic band gap and dielectric function. The binding energy and interlayer distance indicate that germanene and AlAs monolayers in the AAI pattern are bound together via van der Waals interaction with a maximum indirect-gap of 0.494 eV, which is expected to have potential application in the field of field-effect transistors. Under a negative E-field and compressive strain, the bandgaps of the AAI-stacking show a near-linear and linear decrease behavior, respectively, whereas the response of the bandgaps to a positive E-field and tensile strain displays a dramatic and monotonous decrease relationship. The work function of the AAI-stacking is calculated to be 4.35 eV smaller than that of individual monolayers. Besides, the optical properties are also calculated. The imaginary parts of the dielectric function of the germanene/AlAs heterobilayer exhibit a significant enhancement in comparison with the considered monolayers, indicating the improvement of the capability of absorbing photons. In particular, the imaginary part of the dielectric function of the heterostructure is enhanced with the increase of E-field and mechanical strain, which suggests that the optical properties of the heterostructure can be improved by E-field and mechanical strain. Simultaneously, a red-shift or blue-shift can be observed with the changes in E-field and mechanical strain. All these nontrivial and tunable properties endow the AlAs/germanene nanocomposite with great potential for FETs, strain sensors, photocatalysis, field emission, energy harvesting, and photonic devices.

Graphical abstract: An AlAs/germanene heterostructure with tunable electronic and optical properties via external electric field and strain

Supplementary files

Article information

Article type
Paper
Submitted
13 juil. 2016
Accepted
02 août 2016
First published
02 août 2016

J. Mater. Chem. C, 2016,4, 8171-8178

An AlAs/germanene heterostructure with tunable electronic and optical properties via external electric field and strain

C. Tan, Q. Yang, R. Meng, Q. Liang, J. Jiang, X. Sun, H. Ye and X. P. Chen, J. Mater. Chem. C, 2016, 4, 8171 DOI: 10.1039/C6TC02951E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements