Rainbows on demand

The information revolution – is the most profound transformation of our culture and industry since the industrial revolution, fundamentally changing the way in which we deal with information and operate as human beings. This revolution is driven by technological advances in how data signals are transmitted, manipulated and received. In this project, we aim to create photonic circuit technologies that will generate hundreds of coherent laser lines from a single semiconductor chip. This will be achieved by creating resonant modulators and nonlinear waveguides with unprecedented efficiency and innovative monitoring and control techniques. These photonic chip comb sources will be inexpensive, compact and energy efficient with transformative impact in spectroscopy, microscopy, precision measurement, quantum computing and ultra-fast optical fibre communications.

We are looking for one highly motivated and passionate PhD student to become part of our team working with designers and ultrafast network system integrators, but particularly focussing on fabrication and realising experimental prototypes of our innovative photonic chip platforms.

The project is supported by the Australian Government through the Australian Research Council Discovery Project and takes places in the Integrated Photonics and Applications Centre (InPAC) at RMIT University. The projects will harness the world leading Micro Nano Research Facility (https://www.rmit.edu.au/mnrf ) and the Melbourne Centre for Nanofabrication (http://nanomelbourne.com).

The successful applicants will learn important research skills in the field of integrated photonics, but also other soft skills such as engaging with both industrial and academic end-users, writing of reports, giving presentations and promoting their work and working towards project milestones within timeframes. The knowledge and key skills that you will gain during your PhD studies will set you up for an inspiring career and would be particularly suitable if you have ambition to join the emerging and rapidly growing Integrated Photonics segment within the broader global high tech industry.

Please contact Dist. Prof. Arnan Mitchell or Dr. Andy Boes for more information.

Advanced Integrated Photonics Circuits for Future Navigation Systems

WDriverless cars are almost real, but the ability for cars to rapidly predict the location of other traffic and obstacles in real time remains a challenge. Traditional GPS position has insufficient speed, resolution and robustness for this purpose and so RMIT is working with Advanced Navigation Pty Ltd to create low-cost positioning systems based on integrated photonic circuits.

We are looking for highly motivated and passionate PhD students who will create new positioning systems based on integrated photonic chips. The PhD students will be exposed to conceptual design, simulation and optimisation, as well as fabrication, characterisation and interfacing of the integrated photonic chips.

The project is supported by Advanced Navigation and takes places in the Integrated Photonics and Applications Centre (InPAC) at RMIT University. The projects will harness the world leading Micro Nano Research Facility (https://www.rmit.edu.au/mnrf ) and the Melbourne Centre for Nanofabrication (http://nanomelbourne.com). The PhD students will also work closely with the Industry Partner, Advanced Navigation (Sydney, Australia) to test the devices in real world applications.

The successful applicants will learn important research skills in the field of integrated photonics, but also other soft skills such as engaging with end-users, which includes writing of reports, giving presentations and working towards project milestones within timeframes. The knowledge and key skills that you will gain during your PhD studies will set you up for an inspiring career in the quickly growing field of Integrated Photonics and the broader high tech industry.

Please contact Dist. Prof. Arnan Mitchell or Dr. Andy Boes for more information.

Development of a biosensor system to predict type I diabetes susceptibility

The incidence of Type 1 diabetes is escalating globally (increasing by 2% p.a. in Australia). 542,000 children worldwide have type 1 diabetes and several millions are at risk of type 1 diabetes (IDF 7th ed Atlas 2015); however diagnosis usually only occurs very late in the development of the disease exposing children to major irreversible health risks due to complications before treatment can even be considered. The development of a kit to predict diabetes will allow stratification of individuals “at risk” of T1D and identify those who need appropriate care/medication to retard the development of type 1 diabetes and prevent unnecessary complications.

We are seeking talented and passionate PhD candidates to join our team. The successful candidate will be enrolled in a multidisciplinary project spanning design and fabrication of silicon chip based photonic sensors, signal processing, automated microfluidic integration, chemical functionalization and clinical deployment. We offer a dynamic environment and the opportunity to work on an innovative scientific project addressing a relevant clinical problem: the early diagnosis of type I Diabetes.

The project seeks the identification of a pre-established type I Diabetes signature of microRNAs1 and cell-free (cf)DNA sequences by on chip sample preparation and multiplexed analysis to enable point of care deployment. This will facilitate improved diagnostic and monitoring tool for diabetes prediction.

The main objectives are:

1) Design, fabrication and optical characterisation of sensitive Photonic sensor devices that allow for multiplexed analyses.

2) Design, fabrication and characterization of microfluidic devices for on chip sample preparation such as blood/plasma separation, nucleic acid extraction and purification, and interfacing to array microfluidics for biosensing.

3) Interrogation of photonic biosensors using sophisticated signal processing/imaging approaches.

4) Design and assessment of diagnostic methodologies involving adequate sensor surface chemistry functionalization and validation for their implementation in biomedical and clinical settings.

We are looking for versatile and independent researchers with a solid background in related topics. If your background fits in one or more of the objectives pursued in this project do not hesitate in applying using this form.

Please contact Dist. Prof. Arnan Mitchell or Dr. Cesar S Huertas for more information.

Programmable Silicon Photonics

Silicon Photonics is an emerging technology which allows wires connected to silicon chips to be replaced by optical fibres. Silicon photonics has the potential to increase the performance of data centres and will eventually replace copper wires in computers. In addition, silicon photonics potentially can be used in many other applications, including bio-sensing, signal processing and quantum communications. Using the same manufacturing facilities as making integrated electronic circuits, sophisticated silicon photonic chips can be manufactured in high volume with low cost. Due to some unique material properties, many photonic components can be integrated in a small footprint, enabling the creation of compact photonic devices but with sophisticated functionality that cannot be achieved with other photonic technologies.

Although many silicon photonic circuits have been demonstrated, most of these are in the form of purpose built application-specific designs that are only fit for a single purpose. The functionality of such devices are fixed when the devices are designed and fabricated. Changing the circuit functionality requires an entirely new device to be designed and fabricated. If photonic circuits can be made reprogrammable similar to Field Programmable Gate Array (FPGA) in electronic devices, it would be easy, quick and low cost to prototype different photonic functions on the same device in which the circuit function is redefined by the users after the device has been fabricated.

This project aims to investigate technologies to allow the functionality of silicon photonic circuits being reconfigurable or programmable. You will learn about silicon photonics design and methods for fabrication. You will work closely with our team to develop technologies to change the configuration of a silicon photonic circuit. These technologies will then be applied to demonstrate reconfigurable/programmable silicon photonic devices using traditional silicon photonic waveguide device topologies or our recently discovered lateral leakage effect. You will also have opportunities to collaborate and visit other world leading researchers in integrated photonics and silicon photonics in the Europe.

The project will be conducted within RMIT's Integrated Photonics and Applications Centre (InPAC) directed by Distinguished Prof Arnan Mitchell. This centre has expertise in integrated photonic chip simulation and design, fabrication and testing and packaging and interfacing enabling research from novel device concepts to realising practical solutions for real world applications.

Please contact Dr. Thach Nguyen or Dist. Prof. Arnan Mitchell for more information.

Photonic signal processing using broadband optical frequency comb

Many applications, including radar mapping, precision synchronization, environmental measurement, imaging as well as the realization of advanced modulation formats for ultrahigh bandwidth digital communications, require the generation, analysis and processing of analogue RF signals in wide bandwidth. Processing wide bandwidth signals in the electrical domain is still challenging due to limited bandwidth of electronic circuits and introduction of digital quantisation noise. Due to the virtually unlimited bandwidth and ultralow noise available in the optical domain, optical signal processing is a very attractive alternative to electronic counterparts. Many signal processing functions have been demonstrated using optics; however, often multiple discrete optical channels with their own laser diodes must be used. This typically results in a very high cost, complexity and energy consumption and footprint. Recently, ultra-broadband optical frequency combs have been demonstrated that can produce over one hundred stable and high quality comb lines – each like a coherent laser source. This technology opens up opportunities to conceive practical and sophisticated photonic signal processors with small foot-print which can be robustly integrated into integrated photonic devices with no moving parts. This research project will investigate novel methods to implement high speed, reconfigurable optical signal processors using the integrated optical frequency comb source. You will investigate photonic techniques to manipulate signals in both the temporal and frequency domains. You will apply the conceived techniques to demonstrate several practical applications in wireless and optic fibre communications as well as radar and remote sensing using the state of the art equipment in the photonic laboratory at RMIT. The opportunity to integrate entire systems as a single compact photonic chips will be available in the final stage of the project.

Please contact Dr. Thach Nguyen or Dist. Prof. Arnan Mitchell for more information.

Integrated photonic devices and circuits harnessing novel phenomenon

Micro-technology has underpinned the information revolution, enabling exceptionally precise and almost incomprehensibly complex microelectronic systems to be mass-manufactured, reliably and at low-cost using standard complementary metal-oxide-semiconductor (CMOS) wafer processing. Integrated photonics has emerged as a successor to integrated electronics, enabling ultra-high speed information transfer through a single optical fibre [1]. Integrated photonics is also attractive to non-data transfer applications, with a particular emerging opportunity being bio-sensing.

Our team at RMIT has pioneered research into an unusual phenomenon in integrated photonics, particularly in silicon photonics, called lateral leakage behaviour and bound states in the continuum [2, 3]. We are seeking talented and passionate PhD candidates to join our team to explore this phenomenon in the emerging integrated photonic waveguide platform Lithium Niotate on Insulator (LNOI) [4] and to create new integrated photonic devices and circuits harnessing this phenomenon. The possibility of utilising the strong electro-optic and nonlinear effects of this waveguide platform to achieve high speed data modulation, programmable/reconfigurable integrated photonic circuit, dynamic filtering functions will also be investigated.

This project will be conducted within the Integrated Photonics and Applications Centre (InPAC, https://www.inpac.org.au/) at RMIT. This centre has expertise in integrated photonic chip simulation and design, fabrication and testing and packaging and interfacing enabling research from novel device concepts to realise practical solutions for real world applications. The integrated photonic chips will be realised using the state-of-the-art facilities at the RMIT Micro-nano Research Facility (MNRF).

References:

[1] Hochberg, M., Baehr-Jones, T. “Towards fabless silicon photonics,” Nature Photon, 4 (2010).

[2] Nguyen, T.G., Ren, G., Schoenhardt, S., Knoerzer, M., Boes, A., Mitchell, A., “Ridge Resonance in Silicon Photonics Harnessing Bound States in the Continuum”, Laser and Photonics Reviews, 13 (2019).

[3] Nguyen, T.G., Boes, A., Mitchell, A., “Lateral Leakage in Silicon Photonics: Theory, Applications, and Future Directions,” IEEE Journal of Selected Topics in Quantum Electronics, 26 (2020).

[4] Boes, A., Corcoran, B., Chang, L., Bowers, J., Mitchell, A., “Status and Potential of Lithium Niobate on Insulator (LNOI) for Photonic Integrated Circuits,” Laser and Photonics Reviews, 12 (2018).

Please contact Dr. Thach Nguyen or Dist. Prof. Arnan Mitchell for more information.

Integrated photonic frequency comb sources

In many photonic applications, including wavelength division multiplexing ultra-high speed optical communications, optical signal processing, spectroscopy, the generation of high quality light sources with many different frequencies is often required [1, 2]. The brute force approach of using multiple discrete laser diodes to create optical frequency combs typically results in very high cost, complexity, energy consumption and footprint systems. Recently, integrated ultra-broadband optical frequency combs have been demonstrated that can produce over one hundred stable and high quality comb lines – each like a coherent laser source [3].

This project aims to investigate high-quality optical frequency comb sources that can be generated from a single integrated photonic chip using the new silicon nitrite waveguide platform being developed at RMIT [4]. The possibility of integrating the on-chip comb sources with other devices and components to form sophisticated integrated photonic circuits in single compact photonic chips for applications in signal processing, data communications and sensing will also be considered.

This project will be conducted within the Integrated Photonics and Applications Centre (InPAC, https://www.inpac.org.au/) at RMIT. This centre has expertise in integrated photonic chip simulation and design, fabrication and testing and packaging and interfacing enabling research from novel device concepts to realise practical solutions for real world applications. The integrated photonic chips will be realised using the state-of-the-art facilities at the RMIT Micro-Nano Research Facility (MNRF).

References:

[1] Nguyen, T.G., Shoeiby, M., Chu, S.T., Little, B.E., Morandotti, R., Mitchell, A., Moss, D.J., “Integrated frequency comb source based Hilbert transformer for wideband microwave photonic phase analysis”, Optics Express, 23 (2015).

[2] Corcoran, B., Tan, M., Xu, X., Boes, D., Wu, J., Nguyen, T.G., Chu, S., Little, B., Morandotti, R., Mitchell, A., Moss, D., “Ultra-dense optical data transmission over standard fibre with a single chip source, ” Nature Communications, 2020.

[3] Gaeta, A. L., Lipson M., and Kippenberg, T. J., “Photonic-chip-based frequency combs,” Nat. Photonics 13 (2019).

[4] Frigg, A.Boes, A., Ren,G, , Nguyen,T.G., Choi, D. Y., Gees, S., Moss, D. and Mitchell, A., “Optical frequency comb generation with low temperature reactive sputtered silicon nitride waveguides, ” APL Photonics, 5 (2020).

Please contact Dr. Thach Nguyen or Dist. Prof. Arnan Mitchell for more information.

Micro/nano fabrication for hybrid integration

Active optical components in photonic circuits are weak or missing pieces of the current silicon photonic technology. Such pieces are needed for the generation, detection and manipulation of light on chips. InPAC have started addressing this roadblock by heterogeneously integrating functional optical materials, such as chalcogenide glass and emerging novel two-dimensional materials onto integrated silicon photonic platforms, providing an unprecedented electronic and photonic laboratory on a chip to study these materials and to utilize their unique properties, realizing integrated optical lasers, amplifiers, modulators and detectors for applications in defence, data communications and biotechnology. This project is to develop the novel hybrid integration platform in InPAC. The InPAC centre has a long success history on the integrated optics for different applications for more than three decades. Through this project, we will continue to elongate the legacy for other decades. Therefore, we need highly motivated students who have interest in micro-nano fabrication and using such optical platform to realise practical applications such as data communications, and biomedical sensing.

Please contact Dist. Prof. Arnan Mitchell or Dr. Guanghui Ren for more information.

Competitive Scholarships at RMIT

Thanks for your interest in studying with our group. In Australia, groups are not generally provided with PhD scholarships to allocate, instead students must compete for scholarships which are offered centrally. You can read about RMIT central scholarships here.

Application for a scholarship requires you to apply for a place - this is a multi-step process, requiring you to:

1) Select a project from the published project list using the button below (for projects within our centre, search for 'InPAC' or the last name of the project supervisor). The discipline is 'Electronic and Telecommunications Engineering'.

PhD projects in Optical Communication

This is an open call of PhD projects in optical communication.

Internet traffic is growing by 25% each year as society becomes increasingly connected, driven by the needs of our increasingly connected society. The abrupt shift to remote work at the start of 2020 has given us a glimpse of the capacity crunch we could be facing in the near future, as high-speed 5G wireless connections, self-driving cars and the internet of things put more stress on our networks.

To support this demand, we need to explore new technologies that can change the way we use our optical fibre networks. At InPAC, we're looking at photonic technologies to address issues in our optical communications systems with optical physics. Our goal is to provide technology options that can increase data carrying capacity, while decreasing power consumption, size and potentially cost.

We're investigating systems that generate the equivalent of hundreds of lasers from a single device, that allow massive data rates with inexpensive laser sources, fix unknowable distortions from transmission in optical fibres automatically, and testing novel technologies in real-world fibres.

As part of the team, you will learn how to build and characterize state-of-the-art optical communication systems, learn relevant skills in communications theory and digital signal processing, and gain insight into some novel physics that underpin our photonic approaches. You'll be part of international team, learn how to co-ordinate and manage your own research projects, and do all of the things that make a PhD a real 'research apprenticeship'.

Please contact Dr. Bill Corcoran and Dist. Prof. Arnan Mitchell for more information.