We are looking for a PhD student to work in the area of nanophotonics and plasmonics. In this experimental project, metallic nanocavities, metasurfaces and/or 2D materials will be used to confine light and enhance light-matter coupling at the nanoscale, with the aim of detecting mid-infrared (MIR) signatures of single molecules [1-5]. The project is part of a UKRI Future Leaders Fellowship.
Detecting MIR light, where molecular vibrations act as chemical fingerprints, normally requires cooled detectors to suppress thermal noise. We take a different route: molecular frequency upconversion. Molecules placed in a nanocavity that confines both MIR and visible light absorb MIR photons through their vibrations and emit visible photons, which can be detected with single-photon sensitivity at room temperature [1,4]. This allows both the detection and the spectroscopy of individual molecules, with wide applications in sensing, chemical analysis and biological imaging.
The applicant should have completed (or be close to completing) an undergraduate degree in Physics, Materials Science, Physical Chemistry or a related physical science, preferably with first-class honours or equivalent. Strong analytical and experimental skills are desired. Details of the project will be agreed with the successful candidate to tailor the research to their interests.
The student will work on understanding how MIR and visible light are simultaneously confined in nanometre-scale gaps, and how this dual confinement controls the efficiency of upconversion and detection. They will build and develop optical microscopy and spectroscopy setups to probe these nanocavities, spanning the visible to the mid-infrared, and will study how the response changes as a function of temperature. This will give insight into the role of molecular vibrations, thermal population and noise in the detection process. The work also involves fabricating and self-assembling plasmonic nanocavities, and exploring chiral and other tailored nanostructures [3].
The project will take place in the research group of Dr Rohit Chikkaraddy (https://www.birmingham.ac.uk/staff/profiles/physics/chikkaraddy-rohit.aspx), which is part of the Metamaterials and Nanophotonics Research Centre (https://www.birmingham.ac.uk/research/activity/physics/quantum/metamaterials/index.aspx) in the School of Physics and Astronomy at the University of Birmingham, UK. The thesis is strongly multidisciplinary, and candidates from physics, materials science and chemistry are welcome. You will join an active, international research group and will be supported in developing a personal vision and an autonomous scientific profile, as well as industrial links and scientific collaborations.
The University actively supports equality, diversity and inclusion and encourages applicants from all sections of society. In line with the Department’s Athena SWAN programme, we particularly encourage female candidates to apply.
Funding: Funding is available for UK nationals. For details of the funding, advice on making your application or any other informal enquiries, please contact Dr Rohit Chikkaraddy at r.chikkaraddy@bham.ac.uk.
You can apply by clicking the 'Apply' button above, clearly stating the title of the project, the name of the supervisor (Dr Rohit Chikkaraddy) and the Metamaterials and Nanophotonics Research Centre.
References
[1] Chikkaraddy, et al. “Single-molecule mid-infrared spectroscopy and detection through vibrationally assisted luminescence”, Nature Photonics, 17, 865 (2023).
[2] Chikkaraddy. “Single molecule ready to couple”, Nature Physics, 20, 694 (2024).
[3] Hou et al. “Extreme optical chirality from plasmonic nanocrystals on a mirror”, Nano Letters, 25, 1158 (2025).
[4] Xomalis et al. “Detecting mid-infrared light by molecular frequency upconversion in dual-wavelength nanoantennas”, Science, 374, 1268 (2021).
[5] Chikkaraddy et al. “Single-molecule strong coupling at room temperature in plasmonic nanocavities”, Nature, 535, 127 (2016).
