Wideband All-Fibre Polarisation-Entangled Photon Pair Sources for Quantum Optical Experiments and Quantum Information Processing

This PhD project at the University of Southampton, within the EPSRC Centre for Doctoral Training in Quantum Technology Engineering, focuses on developing wideband all-fibre polarisation-entangled photon pair sources for advanced quantum optical experiments and quantum information processing. The research aims to create fibre-based entangled photon sources using poled silica fibre technology, enabling direct generation of entangled photon pairs in optical fibres. This approach supports the construction of low-cost, versatile sources for quantum applications, including quantum communication, sensing, and metrology. The project addresses the challenge of maintaining high entanglement quality and reliability over a broad spectral range, typically requiring compensation steps in conventional systems. By leveraging type-II spontaneous parametric down conversion (SPDC) in nonlinear materials with low group birefringence, the project seeks to achieve broadband polarisation-entangled biphotons without compensation, a condition readily met in optical fibre-based systems. These systems offer advantages such as compatibility with telecom fibre networks and elimination of bulky free-space optics. The project will develop all-fibre sources based on periodically poled silica fibre (PPSF) technology, involving the design, fabrication, optimisation, characterisation, and deployment of PPSF devices in various quantum applications. Students will receive substantial training in scientific, technical, and commercial skills. The position is open to UK, EU, Horizon Europe, and international students, with UK students eligible for a competitive UKRI TechExpert stipend of approximately £31k per year for four years. Studentships at the UKRI base rate are available for EU and international students, and overseas applicants with external funding are encouraged to apply. Entry requirements include an undergraduate degree with at least a UK 2:1 honours or international equivalent. Applications should be submitted via the university's online portal, including a CV, two academic references, degree transcripts/certificates, and English language qualification if applicable. The university supports equality, diversity, and inclusivity, considers personal circumstances, and offers part-time study options. The application deadline is 31 July 2026, with an earlier deadline of 31 March 2026 for international applicants.