New Paper: Defect-Free Axially Stacked GaAs/GaAsP Nanowire Quantum Dots with Strong Carrier Confinement

Transmission electron microscopy and room-temperature photoluminescence of a dot-in-wire structure.

In a new collaboration between Yunyan Zhang and Profs. Huiyun Liu (UCL), Ana Sanchez (Warwick) and David Mowbray (Sheffield) we report the fabrication and measurement of a GaAs/GaAsP quantum dot-in-wire structure in Nano Letters.

While many material architechtures have been explored for single photon emission, the GaAsP-GaAs system provides strong carrier confinement and sharp interfaces, and can be grown directly onto a silicon substrate. This is a new route to silicon integrated single photon devices.

Reference: Defect-Free Axially Stacked GaAs/GaAsP Nanowire Quantum Dots with Strong Carrier Confinement, Yunyan Zhang, Anton V. Velichko, H. Aruni Fonseka, Patrick Parkinson, James A. Gott, George Davis, Martin Aagesen, Ana M. Sanchez, David Mowbray, and Huiyun Liu, Nano Lett. (2021), DOI: 10.1021/acs.nanolett.1c01461

Learning through Research Internship available

A student experience intership is available in the group for a period of 8 weeks over summer 2021. This paid position is available to any Manchester undergraduate student who is not currently in their final year. They are designed to provide experience of academic research to undergraduates who are considering this as a career choice, and will involve a real research project working alongside PhD and postdoctoral level researchers.

This project “Making Nanomaterial Data Public: An Open-Source Toolbox” will build on our new nanomaterials database to explore how to best make this data open-source, to be used for materials research or data-science applications. It would suit students interested in data science and nanotechnology and with some ability in python/jupyter.

For more information including an application pack, see https://careerconnect.manchester.ac.uk/leap/jobSearch.html?id=1715&service=Careers+Service

Welcoming back returning MPhys students

The group welcomes back our returning MPhys students who will continue on their projects this semester. This includes:

Big-data for nano-electronics – development of machine-learning tools for analysis of imaging and spectroscopic data for nanotechnology
Rafe Whitehead, Thomas Blackmore, Jonathan Ryding
Earth’s-field NMR – design and construction of an NMR system to operate in the Earth’s magnetic field
Luis Pedro Martins Mestre, Alexander O’Sullivan, James Overend, Ewan Kilpatrick
i-TCSPC analytics – studying single photon sources with inteferometric single-photon counting
Jake Manning

New Review : Measuring, controlling and exploiting heterogeneity in optoelectronic nanowires

Interwire and intrawire inhomogeneity

Group PhD students Ruqaiya Al-Abri and Hoyeon Choi have written an invited review article for JPhys Photonics, published today.

Lead author Ruqaiya Al-Abri describes this work:

Among the one-dimensional structures, semiconductor nanowires have attracted great attention; from the growth process to the production of functional devices they have been widely studied. The growth condition of the nanowires can lead to non-uniformity (disorder) in the crystal structure, morphology, and geometry of the nanowire. Consequently, this affects the functionality of individual and/or ensembles of nanowires. However, researchers have benefited from disorder; it has been shown that disorder can enhance the performance of ensemble of nanowires such as in photovoltaic devices. This review article attempts to understand the disorder in these structures, investigates the origin of the inhomogeneity within “interwire” and between “intrawire” nanowires, and outlines different approaches to correlate disorder to functional parameters and hence optimize the performance of the nanowires.

Reference: Measuring, controlling and exploiting heterogeneity in optoelectronic nanowires, Ruqaiya Al-Abri, Hoyeon Choi and Patrick Parkinson, JPhys Photonics, (2021) DOI:10.1088/2515-7647/abe282

EPSRC-funded PhD position now available

A fully funded EPSRC studentship (DTP) will be available in the group for a September 2021 start. This studentship is associated with the “Big-data for nano-electronics” project, and is open to UK-based applicants (EU applicants living in the UK may also be eligible for some support).

The project will develop a framework for producing and analysing high-throughput imaging and spectroscopy data for inhomogeneous nano-electronic devices, and will include both experimental and computational work.

In particular, students with a good first degree or MSc in physics, electronic materials, nanotechnology or photonics are encouraged to apply.

For further details, please contact Patrick. Applications must be made via the University site.

2020.S7 – Group MPhys Students

The group welcomes a bumper set of new MPhys (Masters project) students on a range of projects. Welcome to all students!

Big-data for nano-electronics – development of machine-learning tools for analysis of imaging and spectroscopic data for nanotechnology
Rafe Whitehead, Thomas Blackmore, Omar Ahmed, Jonathan Ryding
Earth’s-field NMR – design and construction of an NMR system to operate in the Earth’s magnetic field
Luis Pedro Martins Mestre, Alexander O’Sullivan, James Overend, Ewan Kilpatrick
i-TCSPC analytics – studying single photon sources with inteferometric single-photon counting
Jake Manning