Compact Terahertz Spectrometer based on Metasurfaces

Terahertz (THz) spectroscopy holds significant importance owing to the abundance of molecular and atomic fingerprint lines within this frequency range. In astronomy, THz spectroscopy provides a powerful probe of rotational and vibrational transitions of molecules, offering insights into star and planet formation as well as the physical and chemical processes in galactic and interstellar environments.
 

Conventional THz spectrometers typically rely on multiple free-space optical elements or moving parts, which makes them bulky and challenge to integrate into compact systems. Metasurfaces, planar optical components composed of subwavelength nanostructures, have recently emerged as a powerful new approach for controlling the polarization, phase, and amplitude of light with unprecedented flexibility. These advances open the door to the design of highly compact and versatile spectroscopic instruments.

This PhD project will focus on the development of a proof-of-concept compact THz spectrometer based on metasurfaces. The project will span scales from designing and optimizing nanophotonics to integrating and characterizing a full spectrometer system. We are seeking a motivated candidate with a strong interest in experimental physics. Applicants from broad backgrounds, including astronomy, optics, electrical engineering are encouraged to apply.

Contact: Dr. Yuan Ren

Rydberg atomic receivers for submillimetre astronomy

The submillimetre and terahertz (THz) regime provides a powerful window on the cold universe, capturing thermal emission from interstellar dust and a wealth of molecular and atomic spectral lines. Observations at these wavelengths therefore provide key information on the physical and chemical conditions of the interstellar medium, and on the processes by which stars and galaxies form and evolve.

Rydberg atoms offer a new approach to electromagnetic-field detection in this regime. Highly excited atoms in a vapour cell interact strongly with an incident electromagnetic field, modifying their energy-level structure and optical response. The response can be tuned to different frequencies by selecting appropriate Rydberg transitions, covering a wide THz range, and offers a route to self-calibrated, SI-traceable measurements of electromagnetic fields.

This PhD project will explore the potential of Rydberg atomic sensing for submillimetre astronomy. The work will investigate key aspects of system performance through a combination of modelling, design and experimental characterisation, and assess its potential for future astronomical applications.

We are seeking a motivated candidate with a strong interest in experimental physics and instrumentation. Applicants from a broad range of backgrounds, including astronomy, quantum optics, atomic physics and electrical engineering, are encouraged to apply.

Contact: Dr. Yuan Ren

Mid-wavelength IR spectroscopy to understand and mitigate parasitic emission in thermography diagnostics

Infrared imaging is essential for understanding and protecting plasma-facing components in fusion experiments, but interpreting these measurements becomes challenging under the highly radiative plasma conditions relevant to future fusion reactors.

This PhD will develop a new mid-wave infrared (3–5 µm) spectroscopic diagnostic for MAST Upgrade to investigate the spectrum and physical origins of divertor plasma emission. You will design, assemble and commission the instrument, participate in experimental campaigns at UKAEA Culham, and analyse the resulting spectra. The measurements will be used to develop improved techniques for separating plasma emission from surface temperature measurements and to create predictive models that can inform the design of infrared diagnostics for future fusion devices. The project combines optical instrumentation, plasma physics, spectroscopy and experimental fusion research.

Contact: Dr. Rob Harris

Forecasting Atmospheric Optical Turbulence for Astronomy and Space Applications

Can we predict how atmospheric turbulence will affect our ability to communicate with satellites, observe the Universe or track objects in orbit? Atmospheric turbulence limits free-space optical communications, astronomy and optical space surveillance, yet predicting instantaneous turbulence at a particular location remains challenging. In this project, you will investigate how distributed turbulence measurements, meteorological forecasts and machine learning can be combined to address this challenge. The project combines hands-on optical instrumentation, data acquisition and analysis, and machine learning.

The project builds on Durham’s recently developed optical turbulence sensor, which offers a unique capability for 24-hour operation. You will combine its measurements with meteorological measurements and forecasts, using machine learning tools to investigate how accurately turbulence can be forecast over time. We will then investigate whether a wide-area network of autonomous instruments operating 24 hours a day can extend these predictions to locations without dedicated turbulence instrumentation. Finally, we will couple predicted atmospheric conditions to optical propagation models, and explore applications in optical satellite communications, astronomical imaging, and/or space surveillance and tracking (SST).

This project will be in collaboration with the University of Auckland. Students will be based at Durham University, with an academic adviser at the partner institution, and will normally spend around six months undertaking research at the partner university. Students will build an international network of researchers and fellow doctoral students while gaining experience of different research environments and approaches. The placement will be an integral part of the PhD, enabling students to access complementary expertise and facilities and develop collaborations that strengthen their research and future careers.

Contact: Prof. James Osborn

TMA alignment using Machine Learning 
Three-mirror anastigmat (TMA) telescopes can give excellent image quality, but getting all three mirrors properly aligned is challenging: Small errors in the position or orientation of the mirrors can introduce complex aberrations, and different combinations of alignment errors can produce very similar PSFs. This makes it difficult to determine from an image which mirror is misaligned and what correction is needed.

This PhD will look at using machine learning to automatically work out the alignment corrections needed for a TMA from images. A digital twin of the telescope will be developed to simulate different mirror misalignments and the resulting PSFs. These data will then be used to train a machine-learning model to learn which corrections need to be applied to the three mirrors.

A key part of the project will be investigating the use of asymmetric masks on the three mirrors to help break these degeneracies. By introducing a known asymmetry into the pupil, each mirror could produce a more distinctive signature when it is misaligned. This should make it easier for the ML model to identify which mirror needs correcting and by how much.

The final aim would be to develop a fast, image-based approach to telescope alignment that could eventually be used for complex and deployable space telescopes.

Contact: Dr. Cyril Bourgenot

Multiband VIPA-Based High-Resolution Spectroscopy

This project will investigate a new type of compact, high-resolution spectrograph based on a VIPA (Virtually Imaged Phased Array).

The project will investigate novel VIPA-based concepts (TRL 1–3), including a multiband VIPA spectrograph using a filtered camera and a tunable VIPA for fine-tuning the dispersion. Air-spaced and tunable VIPAs have already been explored, but we propose a different approach. Our suggested design will use cryogenic and harsh-environment-compatible PICA shear actuators from PI (Physik Instrumente), resulting in a highly modular and space-compatible system.

The project will involve the design and modelling of high-resolution spectrographs for applications such as in Earth Observation (EO) and ground-based systems. Potential applications include measuring atmospheric gases such as CO₂ and O₂, estimating total atmospheric mass, and studying the effects of clouds and aerosols.

Contact: Dr. Cyril Bourgenot

IMPROVING THE ACCURACY OF DRONE BASED REMOTE
SENSING WITH ASTRONOMICAL INSTRUMENTATION

The recent advances in UAV capability has given the remote sensing community a number of exciting possibilities. Unfortunately, in the context of plant ecology, the realization of this potential has focused on monitoring crop health where the species of plant is known. Furthermore, this monitoring is usually restricted to a small number of wavelengths, resulting in a noisy dataset that is not able to differentiate between plant species or identify pathogens. As such, UAVs have not realised their full potential in UAV-based remote sensing of plants. This unrealised potential also applies to other areas of UAV-based remote sensing such as atmospheric content where UAV technology affords us the possibility of mapping out temporal and spatial variations in atmospheric gas and dust content.

This PhD position will look to combine astronomical instrumentation, UAV technology and machine learning, with a sensor-fusion approach to improve remote sensing capability. To achieve this, your tasks will include developing new imaging capability to mount to UAVs, apply machine learning analysis to remote sensing data sets to improve remote sensing accuracy and conduct simulations to quantify the accuracy of the new remote sensing capability.

Contact: Dr. Anthony Brown

ULTRA HIGH ENERGY NEUTRINO ASTRONOMY WITH
TRINITY

The Trinity telescope is a novel and distinctive approach to observing the neutrino Universe. Trinity detects ultra-high-energy (UHE) tau neutrinos indirectly by observing the Cherenkov flashes from upward-going air showers emerging from the ground. These showers occur when a tau neutrino skims through the Earth’s
crust, interacts to produce a tau lepton, and that tau exits the surface and decays upward into the atmosphere. By placing a wide-field imaging Cherenkov telescope on a mountain and pointing it just below the horizon, Trinity is uniquely positioned to capture these upward-travelling optical flashes. This strategy
adapts proven techniques from ground-based gamma-ray astronomy to the UHE neutrino regime, enabling low background levels and excellent energy and angular resolution. With this approach, Trinity bridges the energy gap between the astrophysical neutrinos observed by IceCube and the extreme energies targeted by future radio-based observatories, giving it a unique and complementary role in global neutrino astronomy.

For this PhD project, you will join the Trinity collaboration and work with data from the Trinity demonstrator telescope to help open the ultra-high-energy neutrino window on the Universe. Supervised by Dr Anthony Brown and working closely with international partners across the USA, Europe, and Japan, you
will play a central role in several core operational and scientific aspects of Trinity.

Your work will focus on developing and applying advanced simulations to quantify Trinity’s sensitivity
and reconstruction accuracy, cleaning and analysing real observational data from the demonstrator, and investigating potential astrophysical sources of UHE neutrinos to interpret these observations. Through this combination of simulation, data analysis, and physical modelling, you will make substantive contributions to Trinity’s scientific output and its evolution toward a full-scale observatory.

Contact: Dr. Anthony Brown

CALIBRATION INSTRUMENTATION FOR THE TRINITY NEUTRINO TELESCOPE

The Trinity telescope is a novel and distinctive approach to observing the neutrino Universe. Trinity detects ultra-high-energy (UHE) tau neutrinos indirectly by observing the Cherenkov flashes from upward-going air showers emerging from the ground. These showers occur when a tau neutrino skims through the Earth’s
crust, interacts to produce a tau lepton, and that tau exits the surface and decays upward into the atmosphere. By placing a wide-field imaging Cherenkov telescope on a mountain and pointing it just below the horizon, Trinity is uniquely positioned to capture these upward-travelling optical flashes. This strategy
adapts proven techniques from ground-based gamma-ray astronomy to the UHE neutrino regime, enabling low background levels and excellent energy and angular resolution. With this approach, Trinity bridges the energy gap between the astrophysical neutrinos observed by IceCube and the extreme energies targeted by future radio-based observatories, giving it a unique and complementary role in global neutrino astronomy.

For this PhD project, you will join the Trinity collaboration and take a leading role in developing and deploying the calibration instrumentation that underpins Trinity’s scientific performance. Working under the supervision of Dr Anthony Brown and collaborating closely with international partners across the USA,
Europe, and Japan, you will help deliver the systems that ensure Trinity’s measurements of ultra-high-energy air showers are precise, stable, and scientifically robust.

Your work will span three major calibration domains. You will design, refine, and operate the camera calibration system, enabling accurate gain, timing, and uniformity measurements across thousands of SiPM pixels. You will develop atmospheric-sensing techniques using controlled light beacons, characterising atmospheric transmission and its impact on Cherenkov signals in real time. And you will pioneer UAV-based mirror alignment, using airborne platforms to map optical throughput and verify the telescope’s point-spread function with unprecedented flexibility. Through this combination of hardware development, field deployment, data analysis, and calibration modelling, you will make foundational contributions to Trinity’s reliability
and scientific readiness as it evolves toward a full-scale UHE neutrino observatory.

Contact: Dr. Anthony Brown