Start date: 1 October 2018 or 1 February 2019
Application deadline: 7 May 2018
Supervisors: Dr V Tamma, Dr H Yu (Univeresity of Portsmouth), Prof G Adesso (University of Nottingham)

Project:

Multiphoton quantum interference is one of the most intriguing phenomena in quantum physics, and is at the very heart of quantum computing and metrology technologies. However, the post-classical sensing and computational capabilities of multiphoton networks are yet far from being fully explored in practical experimental scenarios.

This theoretical project aims to develop scalable sensing and computational techniques based on the use of optimal linear interferometers with experimentally available photonic input states. The main idea is to exploit the full quantum information encoded in the interferometric evolution of the input photonic quantum states by employing novel measurement techniques (e.g. iterative interferometric dynamics, conditional dynamics, multiplexing and correlation measurements sensitive to the photonic inner and spatial modes).

This will enable an enhanced quantum metrological sensitivity with scalable experimental schemes. It will allow the development of new quantum technologies for high-precision phase estimation and imaging boosting sensing and biological applications as well as fundamental tests at the border between quantum mechanics and general relativity.

On the other hand, these interferometer techniques can be employed to achieve quantum computational speed up with resources which are scalable and experimentally available with the current technology. This can lead to scalable experimental demonstrations of quantum computational supremacy without relying on the yet experimentally demanding implementation of a quantum computer.

The PhD student will not only benefit from the supervision and the expertise provided by the supervisory team and from the interactions with the members of their groups, but also, given the experiment oriented character of this project, from already established collaborations with leading experimental groups across four different continents.

In particular, the quantum optics and quantum information group at University of Portsmouth led by Dr. Vincenzo Tamma has been successful in the study of the fundamental physics at the interplay between quantum physics, quantum information, complexity theory, atomic physics and general relativity, as well as at boosting the real-world implementation of quantum-enhanced technologies for applications in quantum computation, quantum communication, simulation of complex quantum systems, high-precision sensing and imaging.

The PhD student will also benefit from the South-East Physics network (SEPnet), which is a regional collaboration of nine universities including Portsmouth. Indeed, the SEPnet graduate network provides technical, professional and leadership skills programme, career advice, including employer engagement, internships and other employer-led workplace experience. Furthermore, the PhD student will have the possibility to participate in the SEPnet summer schools as well as Physics lecture series and colloquia hold by prominent Physics scientists from international leading institutes. She/he will also be encouraged to present her/his work at collaboration meetings as well as research conferences, including SEPnet conferences, and will receive training for outreach research activities to help her/him promote her/his work and develop her/his career.

Applicants should have a good first degree in Physics or a closely related topic, and a strong interest in quantum information and sensing technologies, and quantum optics.

Informal enquiries should be directed to Dr Vincenzo Tamma (vincenzo.tamma@port.ac.uk).

How to apply:

We welcome applications from highly motivated prospective students who are committed to develop outstanding research outcomes. You can apply online at http://www.port.ac.uk/applyonline. Please quote project code MPHY4300518 in your application form.

Funding Notes:

The fully-funded, full-time three-year studentship provides a stipend that is in line with that offered by Research Councils UK of £14,777 per annum.

References:

1. Y. S. Ihn, Y. Kim, V. Tamma, and Y.H. Kim, Second-order temporal interference with thermal light: Interference beyond the coherence time, Phys. Rev. Lett. 119, 263603 (2017)

2. M. D’Angelo, A. Mazzilli, F.V. Pepe, A. Garuccio, and V. Tamma, Characterization of two distant double-slits by chaotic light second-order interference Nature Sci. Rep. 7, 2247 (2017)

3. M. Cassano, M. D’Angelo, A. Garuccio, T. Peng, Y. Shih, and V. Tamma, Spatial interference between pairs of disjoint optical paths with a single chaotic source, Opt. Express 25, 6589 (2017)

4. O. Zimmermann and V. Tamma, Which role does multiphoton interference play in small phase estimation in quantum Fourier transform interferometers?, Int. J. Quantum Inf. 15, 8 1740020

5. V. Tamma and S. Laibacher, Multiboson Correlation Interferometry with Arbitrary Single-Photon Pure States, Phys. Rev. Lett. 114, 243601 (2015)

6. S. Laibacher and V. Tamma, From the Physics to the Computational Complexity of Multiboson Correlation Interference, Phys. Rev. Lett., 115, 243605 (2015)

7. V. Tamma and S. Laibacher, Multi-Boson Correlation Sampling, Quantum Inf. Process. 15(3), 1241-1262

8. M. D’Angelo, A. Garuccio, and V. Tamma, Toward real maximally path-entangled N-photon-state sources, Phys. Rev. A 77, 063826 (2008)

9. D. Braun, G. Adesso, F. Benatti, R. Floreanini, U. Marzolino, M. W. Mitchell, S. Pirandola, Quantum-enhanced measurements without entanglement, https://arxiv.org/abs/1701.05152, to appear in Rev. Mod. Phys. (2018)