I. Solar Water Splitting: Direct solar-to-hydrogen conversion presents the most promising technique for achieving both high efficiency and lower costs by eliminating various efficiency loss mechanisms and reducing capital expenditure. This project aims to demonstrate a photoelectrochemical system using III-V multi-junction semiconductors through cost-effective epitaxial lift-off techniques that are surface modified for robust operation. This project involves material synthesis and fabrications using state-of-the-art fabrication techniques and materials characterisations. Interfacial engineering and catalyst functionalisation of semiconductors will be carried out to achieve effective surface passivation, stabilisation and efficient reaction kinetics.
II. Epitaxial growth of III-V microring lasers for integrated silicon photonics: Selective area growth is a templated growth technique that allows different shapes of structures to be grown at the nano/micro-scale. Optical interconnects and all-optical signal processing using silicon photonics technology is currently enabling optical and data communication at higher speeds, lower power consumption and cost. However, on-chip integrated, high efficiency lasers are still elusive due to mismatch in material platforms between the lasers and silicon substrates. The project aims to investigate the growth and demonstration of compound semiconductor microring lasers on silicon substrates using selective area growth to engineer the shape of the lasing cavity at the nano/micro-scale.
III. UV nano-LEDs: There are many applications that utilise the UV region of the electromagnetic spectrum such as water sterilisation, air purification, surface disinfection, free-space non-line-of-sight covert communication, epoxy curing, counterfeit detection, light therapy and fluorescence identification of biological/chemical agents. Currently nearly all UV lamps generate radiation by means of a gas discharge. They are fragile, bulky, expensive, and contain toxic substances such as mercury or deuterium. Hence there are lots of interests in realizing small, robust and highly portable UV sources. AlGaN is a good candidate as it has a large bandgap that corresponds to the UV range and also the maturity of LED technology. This project aims to (i) synthesise the AlGaN nanowires by MOCVD and understand their properties, (ii) design nanowire LED structures, (iii) fabricate and characterise the performance and properties of these LEDs to understand the underlying physics of the devices.
IV. Electrically injected nanowire lasers for application in nanophotonics: Miniaturisation allows more devices of differing functionalities to be integrated together to perform more tasks simultaneously and also reducing power consumption. Nanowire lasers, which have an extremely small footprint, can be used for integrated on-chip photonic devices for a myriad of applications such as on-chip optical signal processing for mobile/data communications and single photon sources for secure communication. Although optically pumped nanowires lasers have been reported, little progress has since been made toward electrically injected nanowire lasers. Electrically operated nanowire lasers will provide the translational step to bring research outcomes from laboratories to practical applications in our daily lives. This project aims to design, grow (by selective area MOCVD), fabricate and characterise electrically injected lasers.
What we offer:
• Tax-free scholarships
• Support for international conferences travel and research visits
• World-class projects and supervision in a dynamic, interdisciplinary environment.
• Access to nanofabrication facilities and state of the art characterisation techniques
The Australian National University (ANU), is one of the top universities in Australia and was ranked 20th globally in the 2018 QS World University Rankings. The Australian National University provides PhD students with a vibrant research community and outstanding program support.
The Department of Electronic Materials Engineering (EME) is one of the nine departments within the Research School of Physics and Engineering (RSPE). RSPE represents Australia’s foremost university-based research activity in the physical sciences area and hosts a wide array of major multi-million dollar experimental facilities many serving a national research role.
The group at ANU, led by Prof. C Jagadish, has over 25 years of experience in epitaxial growth of III-V materials by MOCVD and semiconductor optoelectronics. It is acknowledged as one of the world leaders in the field of compound semiconductors. EME also hosts one of the nodes of the Australian National Fabrication Facility (ANFF) which houses state-of-the-art nanofabrication equipment. These projects will be supervised by Prof. C. Jagadish, Prof. Hoe Tan, Prof. Lan Fu and Dr. Siva Karuturi.
Applicants must preferably hold a first class Honours degree or Master’s degree in Materials Science, Engineering, Physics or Chemistry. Additionally, applicants must meet the ANU English language requirements.
Women and Australian Aboriginal and Torres Strait Islander people are particularly encouraged to apply.
Send the following to firstname.lastname@example.org
• A one page cover letter including a statement of research interests and why you want to do a PhD
• Curriculum Vitae
• Copies of transcripts and degrees
• Proof of English language proficiency
Please note only shortlisted applicants will be contacted.