Simulating the fabrication of aluminium oxide tunnel junctions

Abstract Aluminium oxide (AlO x ) tunnel junctions are important components in a range of nanoelectric devices including superconducting qubits where they can be used as Josephson junctions. While many improvements in the reproducibility and reliability of qubits have been made possible through new...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	M. J. Cyster, J. S. Smith, N. Vogt, G. Opletal, S. P. Russo, J. H. Cole
Formato:	article
Lenguaje:	EN
Publicado:	Nature Portfolio 2021
Materias:	Physics QC1-999 Electronic computers. Computer science QA75.5-76.95
Acceso en línea:	https://doaj.org/article/4a4e7f41868c48e98bbc1caf555d8d79
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:4a4e7f41868c48e98bbc1caf555d8d79
record_format	dspace
spelling	oai:doaj.org-article:4a4e7f41868c48e98bbc1caf555d8d792021-12-02T13:24:27ZSimulating the fabrication of aluminium oxide tunnel junctions10.1038/s41534-020-00360-42056-6387https://doaj.org/article/4a4e7f41868c48e98bbc1caf555d8d792021-01-01T00:00:00Zhttps://doi.org/10.1038/s41534-020-00360-4https://doaj.org/toc/2056-6387Abstract Aluminium oxide (AlO x ) tunnel junctions are important components in a range of nanoelectric devices including superconducting qubits where they can be used as Josephson junctions. While many improvements in the reproducibility and reliability of qubits have been made possible through new circuit designs, there are still knowledge gaps in the relevant materials science. A better understanding of how fabrication conditions affect the density, uniformity, and elemental composition of the oxide barrier may lead to the development of lower noise and more reliable nanoelectronics and quantum computers. In this paper, we use molecular dynamics to develop models of Al–AlO x –Al junctions by iteratively growing the structures with sequential calculations. With this approach, we can see how the surface oxide grows and changes during the oxidation simulation. Dynamic processes such as the evolution of a charge gradient across the oxide, the formation of holes in the oxide layer, and changes between amorphous and semi-crystalline phases are observed. Our results are widely in agreement with previous work including reported oxide densities, self-limiting of the oxidation, and increased crystallinity as the simulation temperature is raised. The encapsulation of the oxide with metal evaporation is also studied atom by atom. Low density regions at the metal–oxide interfaces are a common feature in the final junction structures which persists for different oxidation parameters, empirical potentials, and crystal orientations of the aluminium substrate.M. J. CysterJ. S. SmithN. VogtG. OpletalS. P. RussoJ. H. ColeNature PortfolioarticlePhysicsQC1-999Electronic computers. Computer scienceQA75.5-76.95ENnpj Quantum Information, Vol 7, Iss 1, Pp 1-12 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	Physics QC1-999 Electronic computers. Computer science QA75.5-76.95
spellingShingle	Physics QC1-999 Electronic computers. Computer science QA75.5-76.95 M. J. Cyster J. S. Smith N. Vogt G. Opletal S. P. Russo J. H. Cole Simulating the fabrication of aluminium oxide tunnel junctions
description	Abstract Aluminium oxide (AlO x ) tunnel junctions are important components in a range of nanoelectric devices including superconducting qubits where they can be used as Josephson junctions. While many improvements in the reproducibility and reliability of qubits have been made possible through new circuit designs, there are still knowledge gaps in the relevant materials science. A better understanding of how fabrication conditions affect the density, uniformity, and elemental composition of the oxide barrier may lead to the development of lower noise and more reliable nanoelectronics and quantum computers. In this paper, we use molecular dynamics to develop models of Al–AlO x –Al junctions by iteratively growing the structures with sequential calculations. With this approach, we can see how the surface oxide grows and changes during the oxidation simulation. Dynamic processes such as the evolution of a charge gradient across the oxide, the formation of holes in the oxide layer, and changes between amorphous and semi-crystalline phases are observed. Our results are widely in agreement with previous work including reported oxide densities, self-limiting of the oxidation, and increased crystallinity as the simulation temperature is raised. The encapsulation of the oxide with metal evaporation is also studied atom by atom. Low density regions at the metal–oxide interfaces are a common feature in the final junction structures which persists for different oxidation parameters, empirical potentials, and crystal orientations of the aluminium substrate.
format	article
author	M. J. Cyster J. S. Smith N. Vogt G. Opletal S. P. Russo J. H. Cole
author_facet	M. J. Cyster J. S. Smith N. Vogt G. Opletal S. P. Russo J. H. Cole
author_sort	M. J. Cyster
title	Simulating the fabrication of aluminium oxide tunnel junctions
title_short	Simulating the fabrication of aluminium oxide tunnel junctions
title_full	Simulating the fabrication of aluminium oxide tunnel junctions
title_fullStr	Simulating the fabrication of aluminium oxide tunnel junctions
title_full_unstemmed	Simulating the fabrication of aluminium oxide tunnel junctions
title_sort	simulating the fabrication of aluminium oxide tunnel junctions
publisher	Nature Portfolio
publishDate	2021
url	https://doaj.org/article/4a4e7f41868c48e98bbc1caf555d8d79
work_keys_str_mv	AT mjcyster simulatingthefabricationofaluminiumoxidetunneljunctions AT jssmith simulatingthefabricationofaluminiumoxidetunneljunctions AT nvogt simulatingthefabricationofaluminiumoxidetunneljunctions AT gopletal simulatingthefabricationofaluminiumoxidetunneljunctions AT sprusso simulatingthefabricationofaluminiumoxidetunneljunctions AT jhcole simulatingthefabricationofaluminiumoxidetunneljunctions
_version_	1718393091949330432

Simulating the fabrication of aluminium oxide tunnel junctions

Ejemplares similares