COMBS Summer Internship Program

Supervisor: Professor Meghan Miller and Dr. Tianwei Sun (ANU)

Project Description: A technology called Distributed Acoustic Sensing (DAS) is a rapidly emerging sensing technique that converts telecommunication fibre-optic cables into thousands of densely-spaced ground-motion sensors using backscattered laser light. Using DAS data recorded on ~25 km of fibre beneath Melbourne this project aims to track storms, in particular, thunderstorms. Lightning can be a significant natural hazard and locating the strikes is of key importance in mitigating the hazard.  This project will use DAS ground motion signals with the aim to triangulate the thunder sources and then correlate them with radar reflectivity. This internship project will showcase the feasibility of effectively tracking lightning with existing optic cables, which could have a broad application, especially in urban areas. 

Tasks:

• Developing python skills to analyse DAS data from the ALiRT fibre.  Collating weather data from the Bureau of Meteorology.  Identification of ground motions associated with thunderstorms. 

Who Should Apply: This project is aimed at   2nd and 3rd year students studying physics, geophysics, mathematics, or engineering, particularly those fascinated by Earth science, environmental geophysics, laser physics and precision measurements. Ideal for those their research skills, such as computational skills working with python on large volumes of data, seismology and multidisciplinary Earth science data. 

Eligibility: students must have completed two years of a STEM based undergraduate degree 

Please send your application for this research project to: Meghan Miller meghan.miller@anu.edu.au

Supervisor: Prof D Lancaster and Dr W. Zhang, Spectroscopy and Microscopy theme (University of South Australia)

Project Description: Complete the build, characterise, and demonstrate an application for a chip based dual frequency comb laser prototype  

Tasks:

• Experimental physics, optics, free-space alignment, laser physics, signal acquisition and processing.  

Who should apply: This project is aimed at   2nd and 3rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those their research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills. 

Eligibility: students must have completed two years of a STEM based undergraduate degree   

Please send your application for this research project to: David Lancaster david.lancaster@unisa.edu.au

Supervisor: Dr. Van Thuy Hoang and Dr. Andy Boes School of Electrical and Mechanical Engineering, Faculty of Sciences, Engineering and Technology, The University of Adelaide, SA, Australia.

Project Description: Optical frequency combs play a crucial role in a wide range of applications, including telecommunications, astronomy, and for this project, metrology. An optical frequency comb is an array of optical frequencies with equal spacing between consecutive lines. The line spacing is referred to as the repetition rate (frep) of the optical frequency comb. They can be generated using mode-locked stable lasers, nonlinear optical waveguides or electro-optic (EO) modulation. For the electro-optic modulation approach, modulators are driven by harmonic radio-frequency (RF) signals. The resulting frequency combs are known as electro-optic frequency combs (EO-combs). Compared to other methods, EO-combs offer ease of operation, high stability, and flexible tuning of frep, across a wide range, from Hz to GHz.

However, a remaining challenge of EO-combs is their narrow spectral bandwidth — the distance between the longest and shortest wavelengths is typically only a few nanometres. Therefore, to expand the application potential of EO-combs, spectral broadening is necessary.

In this project, nonlinear optical fibres are used to broaden the EO-comb spectrum through various nonlinear effects occurring within the fibres. In particular, the internship student will measure spectrum and temporal profile of initial EO-combs, amplify the combs using erbium-doped fibre amplifiers (EDFA) to get EO-combs with high power, and couple the amplified EO-combs to nonlinear fibres for spectral broadening. The internship student also numerically simulates nonlinear phenomena in the fibres and compare the results with experimental data. The resulting broadened EO-combs are attractive for future precision metrology applications such as LIDAR and holography.

Tasks:

• Using Matlab or Python to numerically simulate nonlinear phenomena in fibres.

• Gaining familiarity with advanced optical lab equipment, such as optical fibres, splicers, fibre couplers, lasers, oscilloscopes, and RF devices.

• Characterizing the system to make EO combs

• Setting up a system to broaden the EO-combs spectrum

• Analysing data, comparing experimental and simulation data.

• Writing abstracts and posters, participating workshops/conferences (optional) and writing a report of the internship.

Who Should Apply: This project is aimed at 2nd and 3rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those with research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills.

Eligibility: students must have completed two years of a STEM based undergraduate degree.

Please send your application for this research project to: Andy Boes andy.boes@adelaide.edu.au 

Supervisor: Professor Sumeet Walia (RMIT University)

Project Description: In this project, you will explore the intersection of advanced 2D materials and optical frequency combs (COMBS), focusing on developing a photodetector prototype that broadens the spectral response across the visible to infrared (IR) range. Optical COMBS are a series of equally spaced frequency lines, and their applications span from high-precision spectroscopy to advanced imaging techniques. Your work will centre on integrating low-dimensional materials such as Black Phosphorus (BP) and Indium Selenide (InSe) into a heterostructure to create a photodetector capable of detecting the broad spectral range necessary for COMBS applications. BP is selected for its tunable bandgap and strong absorption in the near-IR, which is critical for detecting lower-frequency comb lines. InSe, with its strong absorption in the visible range, complements BP, enabling the detection of higher-frequency comb lines. The heterostructure of these materials is expected to yield a device with enhanced sensitivity across the entire optical comb spectrum, making it ideal for applications in spectroscopy, telecommunications, and precision metrology. 

Tasks:

• Apply techniques such as mechanical exfoliation to prepare thin flakes of BP and InSe. Fabricate the BP/InSe heterostructures using dry transfer methods, ensuring precise alignment and clean interfaces.  
• Perform photoluminescence (PL) and Raman spectroscopy to verify the quality of the heterostructures and their optical properties in the context of COMBS. 
• Use absorption spectroscopy to measure the photodetector’s response across the visible to IR spectrum, ensuring it covers the broad range of frequencies generated by optical COMBS. 
• Design and fabricate a photodetector prototype that integrates the BP/InSe heterostructure, tailored for detecting the specific frequency lines of optical COMBS. 
• Analyze the photodetector’s performance in detecting different segments of the optical COMB spectrum, focusing on metrics such as responsivity, bandwidth, and signal-to-noise ratio. 

Outcome: By the end of this project, you will have developed a photodetector prototype capable of detecting a wide range of frequencies from an optical COMB, spanning from visible to IR wavelengths. This project will provide you with hands-on experience in the fabrication and characterization of 2D material heterostructures, as well as their integration into devices for cutting-edge optical applications. Your work will contribute to the development of more efficient and sensitive detectors for optical COMBS, with potential applications in spectroscopy, telecommunications, and beyond.

Please send your application for this research project to: Sumeet Walia sumeet.walia@rmit.edu.au

Supervisor: A/Professor Bill Corcoran (Monash University)

Project Description: Microcombs can support massively parallel communications channels, by putting a different set oof data on each line in the comb. However, we can also use the synchronization of phase and frequency between comb lines to work in the very low SNR regime, where coherent addition can pull a signal out of noise. This provides a way to trade off bandwidth for signal-to-noise ratio improvement, which may open the door to greater power efficiency in the links that tie our internet together.  

Tasks:

This project will involve theoretical, numerical and experimental work, to help us start understanding the potential role that coherent addition using microcombs could play in future communications systems. You will be looking into the practical trade-offs between bandwidth and capacity in this new type of system, both experimentally, and numerically, and help gauge where this new technology can provide benefits in fibre optic links 

Who Should Apply: This project is aimed at   2nd year (and beyond) students studying physics, or engineering, particularly those with who’d like to both work in the lab, and do some numerical modelling to understand theory.  

Ideal for those who know a little about optics and/or photonics, and something about communications and signals, and want to get some idea of what working in a university research lab is like.   

Eligibility: Students must have completed two years of a STEM based undergraduate degree.  

Please send your application for this research project to: Bill Corcoran bill.corcoran@monash.edu 

Supervisor: Professor Sumeet Walia (RMIT University)

Project Description:

This project focuses on the design and implementation of a hardware-based artificial intelligence (AI) accelerator using Field-Programmable Gate Arrays (FPGAs), targeting energy-efficient AI applications at the edge. With growing demand for real-time decision-making in autonomous systems, healthcare, robotics, and IoT, there is a critical need for lightweight and reconfigurable AI hardware that can operate under power and resource constraints. 

In this project, you will explore how digital hardware, particularly FPGAs, can be used to implement core components of neural networks directly in logic. Unlike traditional CPU or GPU-based processing, FPGAs offer customizable data paths, parallelism, and low-latency execution that make them well-suited for deploying spiking neural networks (SNNs) and quantized convolutional neural networks (CNNs) on-device. You will start by designing a basic neural processing unit (NPU) architecture using hardware description languages such as Verilog or VHDL. Building on this, you will implement a simplified yet functional neural network model, such as a small CNN or a spike-based classifier, and deploy it on a low-cost FPGA board like the DE10-Nano or Xilinx Zynq. 

The emphasis will be on optimizing the trade-offs between computational precision (e.g., fixed-point vs. floating-point arithmetic), logic resource usage, and inference speed, while ensuring the design remains scalable and adaptable to different AI workloads. Ultimately, this project aims to contribute to the field of neuromorphic and hardware-aware AI design, preparing you to address real-world challenges in edge AI systems. 

Tasks:

Perform a literature review on existing hardware AI accelerators, including SNN and CNN implementations on FPGAs. 

• Design a basic AI accelerator using Verilog/VHDL or high-level synthesis tools, targeting neural operations such as multiply-accumulate and activation functions. 
• Simulate and validate the design using tools such as QuestaSim or ModelSim, followed by hardware synthesis using Quartus or Vivado. 
• Deploy the design on an FPGA platform and test its performance using simple classification tasks. 
• Evaluate performance metrics including power consumption, resource utilisation, latency, and accuracy, and explore potential for on-chip training or adaptation. 

Outcome:

By the end of this project, you will have successfully designed, implemented, and tested a custom AI accelerator on an FPGA platform, capable of performing neural network inference in real time. You will gain hands-on experience in digital hardware design, FPGA programming, and neural network architecture optimisation, skills that are in high demand across the AI hardware and embedded systems industries. 

You will also develop critical insights into the trade-offs between power, performance, and precision in AI hardware, and understand the challenges of implementing machine learning algorithms in constrained environments. The final deliverables will include a functional FPGA-based AI accelerator, a comprehensive technical report detailing the design methodology, and a performance analysis that may serve as the basis for further research or prototyping. 

Please send your application for this research project to: Sumeet Walia sumeet.walia@rmit.edu.au

Supervisor: A/Professor Bill Corcoran (Monash University)

Project Description: When we work on optical communications in university labs, we do a lot of digital signal processing (DSP) on our laptops, which stands in for processes that would normally occur in a specialised chip. Radio-frequency systems-on-a-chip  (RF SoCs) join analogue-to-digital and digital-to-analogue converters (ADCs and DACs) to field-programmable gate arrays (FPGAs). This opens up the possibility to implement DSP in real time on RF SoCs, and then use this information to enable co-processing of communications channels with sensor or timing information from a fibre optic link. 

Tasks:

This project will work on FPGA coding on an AMD RF SoC, to create an “overlay” that can then be accessed for research purposes via python (or similar). This builds on an existing approach being developed in our lab for turning RF SoCs into flexible tools for COMBS science. Specifically, you will be attempting to write a 2×2 MIMO adaptive equaliser, and or carrier recovery DSP. This will adapt existing algorithms implemented in MATLAB and/or python into a real-time version on an FPGA as part of an RF SoC. 

Who Should Apply: This project is aimed at   2nd year (and beyond) students studying engineering, particularly those who would like to get a feel for how some of the skills you learn in engineering fit into research.  

Ideal for those who know have programmed FPGAs before, and want to get some idea of what working in a university research lab is like.   

Eligibility: Students must have completed two years of a STEM based undergraduate degree.

Please send your application for this research project to: Bill Corcoran bill.corcoran@monash.edu 

Supervisor: Kishan Dholakia and Chris Perrella (University of Adelaide)

Project Description: Join the Adelaide node of the ARC Centre of Excellence in Optical Microcombs for Breakthrough Science and learn about frequency comb lasers, their principles of operation and applications in optical spectroscopy and microscopy. In this project, use the concept of laser speckle as a diagnosis approach for a frequency comb. Speckle is a consequence of multiple interference of light creating a granular pattern. This pattern is rich in information about the  light source and can be used in an innovative way to ascertain parameters, which in this case will be the attributes of the comb lines. We may perform detection over the widest possible band while bringing the resolution to the single comb-line level. 

Tasks:

• Learn the physical principles of a frequency comb laser and explore the spectrum of the laser in the lab. 
• Learn the principles of precision measurement of wavelength using speckle 
• Utilize new knowledge in designing speckle based system and performing subsequent data analysis 
• Work in collaboration with the research team to interpret data and refine experimental results.  

Who Should Apply: This project is aimed at 2nd and 3rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those their research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills. 

Eligibility: Students must have completed two years of a STEM based undergraduate degree. 

Please send your application for this research project to: Kishan Dholakia kishan.dholakia@adelaide.edu.au

Supervisor: Dr Moritz Merklein, Dr Ziqian Zhang (University of Sydney) 

Project description: Join the University of Sydney node of the ARC Centre of Excellence in Optical Microcombs for Breakthrough Science (COMBS) and learn about frequency combs, their principles of operation and applications, and be fully immersed in the research group. In this project, you will work with electro-optic modulators to create a frequency comb in optical fibre. You will study the comb in the time and the frequency domain and learn how the two domains are linked. You will then use cavity feedback and nonlinear optical effects in different fibres to further broaden the comb. At the end of the project, you will have created your own frequency comb that can be used in the Centre of Excellence for optical signal processing and generation. 

Tasks:

• Learn the physical principles of electro-optic frequency comb generation with and without resonant feedback and characterise the frequency comb in the time and frequency domain. 
• Learn the principles of nonlinear optics and dispersion and study how nonlinear processes such as self-phase modulation and four-wave mixing in optical waveguides can be utilised to broaden the spectrum of the frequency comb. 
• Collect your own data and work in collaboration with the research team to interpret data and refine experimental results.  
• Package your frequency comb in a portable box so it can be used for future research projects.

Who Should Apply: This project is aimed at   2nd and 3rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those with research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills. 

Eligibility: Students must have completed two years of a STEM based undergraduate degree.

Please send your application for this research project to: Moritz Merklein moritz.merklein@sydney.edu.au

Supervisor: Professor Martijn de Sterke (University of Sydney)

Project Description: The Lugiato-Lefever equation (LLE) describes the generation of frequency combs in a resonator. Since frequency combs result from nonlinear optical processes, the LLE is nonlinear as well. The other ingredient is the dispersion, the wavenumber dependence on frequency of the light in the resonator. The effect of the dispersion enters the LLE through derivative terms. We are interested fractional dispersion, which enters the LLE through fractional derivatives. The aim of this project is to investigate the formation of frequency combs with fractional derivatives and whether they have advantages over conventional frequency combs.

Tasks:

This is a theoretical and numerical project which is based on two pieces of existing software that solves the LLE equation. The first of these can be used to see how the electric field inside the resonator evolves with time. The second can be used to find the steady-state solutions to the LLE equation. The students will use both pieces of software to evaluate the features of frequency combs with fractional derivatives.  

Who Should Apply: This project is aimed at 2nd and 3rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and careful simulations. Ideal for those with computer skills.  

Eligibility: Students must have completed two years of a STEM based undergraduate degree.  

Please send your application for this research project to: Martijn de Sterke martijn.desterke@sydney.edu.au

Supervisor: Dr. Yang Sun and Prof. David J. Moss (Swinburne University of Technology)

Project Description:

Microwave photonic (MWP) signal processing have emerged as a key technology in modern communications, radar, and high-speed signal processing due to their ability to process signals with wide bandwidth, low loss, and immunity to electromagnetic interference. This can support applications from scientific instrumentation, defence systems, and radar-based sensing. Optical microcombs open up new possibilities for implementing MWP signal processing, by offering ultrawide bandwidths far exceeding that of conventional microwave systems and also allowing for wavelength-diversity approaches.  

This project introduces students to the exciting field of optical microcombs and their applications in MWP signal processing. Building on our previous work with the transversal filter structure, students will explore new techniques and applications for microwave signal processing based on optical microcombs. 

Tasks:

Review basic principles of optical microcombs and their role in MWP systems. 

• Students will begin by developing an understanding of optical microcomb generation and the transversal filter structure through guided reading and discussions. 

Simulate the microcomb-based transversal filter for MWP signal processing.

• Students will use MATLAB to simulate the transversal filter structure based on optical microcombs. 

Explore a MWP signal processing function using optical microcomb. 

• Students will generate optical microcombs in the lab and experimentally demonstrate a MWP signal processing function based on the simulation results.  

Who Should Apply: This project is aimed at   2nd and 3rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those their research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills. 

Eligibility: Students must have completed two years of a STEM based undergraduate degree.  

Please send your application for this research project to: David J Moss dmoss@swin.edu.au 

Supervisor: Thach Nguyen, Guanghui Ren, Arnan Mitchell (RMIT University)

Project Description: Photonic chips are similar to microelectronic chips that driving the modern world but using light instead of electrons. Such photonic chips can be used for super-fast telecommunication, biochemical sensing, precision measurement and defence applications. This project will design and characterize the optical components on silicon nitride platform which has wide-transparent window covering from ultra-violet to mid-infrared wavelength.  

Tasks:

• You will learn how to design and then actually make a photonic chip! 
• Create a simple photonic chip layout using design software 
• Deposit a film of silicon nitride on a silicon wafer and characterise this film 
• Pattern the film and etch it to make a photonic integrated circuit 
• Characterize the chip and compare it to predictions form your design. 

Who Should Apply: This project would suit a 3rd year Engineering student who has not yet selected a 4th year ‘capstone’ project (we would like you to consider expanding this project into a capstone project and maybe even consider pursuing this further through postgraduate research).  A keen interest in photonics is important but no prior experience is required (we will train you).  This project could also suit a technology oriented physics student in 3rd year considering pursuing an honours. 

Eligibility: Students must have completed two years of a STEM based undergraduate degree. 

Please send your application for this research project to: Arnan Mitchell arnan.mitchell@rmit.edu.au

Supervisor: Arnan Mitchell and Luke Broadley (RMIT University)

Project Description: Distributed Acoustic Sensing (or DAS) is a technique where laser light can be used to measure vibrations using the same optical fibres that already in the ground carrying the internet that we use every day.  We can use lasers on these same fibres to measure locate vibrations along the fibre and measure the sounds of the city – cars, trams, trains and even foot traffic.  This project will implement a DAS system using our microcomb technology to measure the fibres under Melbourne and will analyse the signals to try to identify the signatures of different types of activity in the city.  

Tasks:

• Help construct a distributed acoustic sensing system in our laboratory  
• Use the DAS system to measure and map vibrations under Melbourne 
• Analyse these measurements and see if patterns can be matched to different activities 

Who Should Apply: This project would suit a 3rd year Engineering student who has not yet selected a 4th year ‘capstone’ project (we would like you to consider expanding this project into a capstone project and maybe even consider pursuing this further through postgraduate research).  A keen interest in photonics is important but no prior experience is required (we will train you).  This project could also suit a technology oriented physics student in 3rd year considering pursuing an honours. 

Eligibility: Students must have completed two years of a STEM based undergraduate degree. 

Please send your application for this research project to: Arnan Mitchell arnan.mitchell@rmit.edu.au

Supervisor: Prof D Lancaster and Dr W. Zhang. UniSA hub, S&T theme 

Project Description: Research towards a chip-based frequency comb based on mode-locked holmium chip lasers   

Tasks:

Experimental physics, optics, free-space alignment, laser physics, laser physics simulation, laser characterisation  

Who Should Apply: This project is aimed at   2nd and 3rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those their research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills.  

Eligibility: Students must have completed two years of a STEM based undergraduate degree. 

Please send your application for this research project to: David Lancaster  david.lancaster@unisa.edu.au

Supervisor: A/Professor Bill Corcoran (Monash University)

Project Description: Soliton crystals are a type of microcomb state that we have often used in COMBS work. Recent work we have done has started to uncover the importance of a physical interaction within the microrings we use to generate microcombs, between two modes of propagation. These interactions give rise to avoided mode crossings. We’d like to investigate further exactly how these avoided mode crossings tie into the microcombs we generate, and what about their properties leads to our combs being “quiet”.

Tasks:

You will work both experimentally and numerically with soliton crystal microcombs, using existing set-ups and scripts, looking at the interaction between soliton crystal; microcombs and avoided mode crossings. You will be able to use both the experimental and numerical platforms to link theory with experiment, and work closely with PhD students to support your learning and develop hands-on research methods.  

Who Should Apply: This project is aimed at   2nd year (and beyond) students studying physics, or engineering, particularly those with who’d like to both work in the lab, and do some numerical modelling to understand theory.  

Ideal for those who know a little about optics, photonics and/or electromag., and want to get some idea of what working in a university research lab is like.   

Eligibility: Students must have completed two years of a STEM based undergraduate degree. 

Please send your application for this research project to: Bill Corcoran bill.corcoran@monash.edu 

Supervisor: Dr Aritra Paul, Dr Isa Ahmadalidokht, Prof. Irina Kabakova

Project Description:

Optical frequency combs are emerging as a powerful approach to spectroscopy and bio-imaging due to their discrete and coherent spectra. It is usually desired to have a broad (up to or beyond octave spanning) comb spectrum to achieve coverage of many absorption lines of interest. To broaden the spectrum of a given frequency comb source, silica photonic crystal fibres (PCF) may be used. This technology is well established and allows some degree of dispersion engineering to achieve desired width and envelope of the supercontinuum optical frequency comb (SC-OFC) output, generated by pumping the PCF with high-power femtosecond and picosecond pulses close to the zero-dispersion wavelength (ZDW). However, the SC-OFC source is typically characterized by large spectral fluctuations due to nonlinear optical effects such as modulation instability (MI), spontaneous Raman scattering and soliton fission. This degrades the coherency of the OFCs and limits their performance in applications like imaging. Effect of input noise, intensity fluctuation, polarization instability and thermal effects finally leads to overall degradation of the SC-OFC finally affecting the overall outcome.

In our experiments of the comb-assisted Brillouin spectroscopy, we observe the effects of noise on the measured Brillouin spectra of standard samples (water, glass, plastic). Deeper understanding of the origin of phase and amplitude noise in the SC-OFC source is this crucial to improve the precision of Brillouin spectroscopy and imaging. This project is aimed at achieving this goal through exploiting nonlinear modelling framework (solving nonlinear Schrödinger equation, or NLSE, in a Matlab code already implemented by the team members).  The program will be adopted to include phase and amplitude noise simulations to explore the aspect of noise in more detail and assist with optimisation of the SC-OFC source. This will then be applied to Brillouin spectroscopy and imaging application producing results with improved quality of imaging, suitable for semi-transparent biological samples.

The internship will begin with laboratory induction and training, to familiarise the candidate with experimental technique and insist in understand of the project scope. A thorough literature review will also be completed at the start of the project.

Tasks:

• Learning basics of nonlinear optics and NLSE model we are using.
• Training on the Brillouin imaging system and operation of OFC source.
• Literature review of the noise characterisation methods for OFCs.
• Numerical modelling of phase noise and coherency of the SC-OFC.
• Additional (but not critical) task will be on expected suggestion for overcoming the noise effects.

Who Should Apply:

This project is aimed at 3^rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those with research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills.

Eligibility: students must have completed two years of a STEM based undergraduate degree, submit all required documents (CV, transcripts, cover letter and at least 1 reference letter).

Please send your application for this research project to: Irina Kabakova irina.kabakova@uts.edu.au

Supervisor: Dr Ziqian Zhang, Dr Moritz Merklein

Project Description:

Acousto-optic (AO) modulation enables precise control over the intensity, frequency, and propagation direction of light, making it a key enabler in advanced photonic systems, including lasers, optical communications, spectroscopy, and quantum optics. This precision control enables AO devices to generate optical frequency combs with a spectral spacing defined by the modulation frequency, thereby breaking free from the rigid constraint of cavity round-trip times typically found in traditional comb sources.

This flexibility opens new pathways for tailoring comb properties to specific applications, such as precision sensing (e.g., RADAR and LiDAR) and optical signal processing (e.g., optical Fourier transform). Moreover, AO modulation can be used to broaden existing combs—such as electro-optic (EO) or micro-combs—and reconfigure their spectral characteristics, enabling extended bandwidth and enhanced functionality for applications in high-resolution ranging, spectroscopy, and beyond.

In this internship project, students will work with pre-configured AO frequency-shifting loop-based combs. The first phase focuses on characterising the comb and implementing a real-time electronic feedback control system to stabilise it against environmental perturbations and suppress noise. In the second phase, an EO comb will be injected into the stabilised AO fibre cavity to achieve spectral broadening. The combined EO-AO system not only surpasses the spectral bandwidth of either source alone but also maintains low-noise performance, making it a powerful platform for advanced photonic applications.

Tasks: The following tasks are designed to guide the whole internship experience while remaining flexible based on each student’s interests and progress. Students are encouraged to focus on a combination of tasks (e.g., 1+2+4 or 1+3+4), depending on preferences.

• Characterise the AO Frequency-Shifting Loop Comb.
• Design and implement an electronic feedback control loop (FPGA-based PID or a similar system) to minimise the noise.
• Inject and align the EO Comb into the AO Loop for broadening.
• Analyse and Compare Spectral Performance

Who Should Apply:

This project is aimed at 2^nd and 3^rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those with research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills.

Students with a passion for bridging practical experimental work with a deeper conceptual understanding of modern photonics and control systems will find this project especially rewarding.

Eligibility: students must have completed two years of a STEM-based undergraduate degree.

Please send your application for this research project to: Ziqian Zhang ziqian.zhang@sydney.edu.au

Supervisor: Martijn de Sterke

Project Description: We are building a fibre-based ring resonator that incorporates a waveshaper. This allows us to program in any net cavity dispersion and therefore to generate a variety of frequency combs that differ qualitatively from conventional ones. The aim of this project is to help characterise the resonator and the resulting frequency combs.

Tasks: In this project, you will work with a fibre resonator and learn how Kerr frequency combs are generated through nonlinear effects. You will operate this system under different driving conditions, such as continuous wave and pulsed driving, and explore how these affect the comb’s shape and stability. You will also learn how feedback systems are used to stabilize the resonator for comb generation.

Who Should Apply: This project is aimed at   2^nd and 3^rd year students studying physics, mathematics, or engineering, particularly those fascinated by laser physics and precision measurements. Ideal for those with research skills, such as laboratory skills working with bulk optics, optical fibres and lasers or simulation skills.

Eligibility: students must have completed two years of a STEM-based undergraduate degree.

Please send your application for this research project to: Martijn de Sterke martijn.desterke@sydney.edu.au