Hybrid Photonics

Recently, we proposed polariton graphs as a new platform for analogue simulation. Polariton graphs benefit by the continuous optical readout of the phase, energy, momentum and spin of the individual polariton vertices, the strong inter-particle interactions −mediated through the exciton component−, room temperature operation −with appropriate choice of materials−, and even the potential for electrical injection utilizing well-developed semiconductor technologies.

Inverse scattering problems, namely reconstructing the shape of objects from their scattered intensity distributions occur in many fields of science and technology, such as tomographic imaging (MRI, CT scan), seismology, single shot X-ray scattering and imaging. Solving the inverse scattering problem, in cases where all the phase information is lost, is generally very difficult. This difficulty is alleviated by resorting to some a priori knowledge such as the boundaries within which the object lies (compact support), sparsity or other spatial features. Under such “restrictions”, it is possible to reconstruct the object using iterative algorithms, such as the well-known Gerchberg-Saxton algorithm. Unfortunately, the algorithms are time consuming and do not always converge to the right solution even with advanced computational resources. In this project, we will design and realise a polariton simulator to address inverse scattering problems with the aim to demonstrate solutions within the coherence lifetime of the polariton condensates (10ths of picoseconds; 6-9 orders of magnitude faster than current supercomputers).

The student will join a strong international team of students, postdoctoral and academic staff working together on many aspects of cutting-edge research in polaritonics, laser physics and quantum simulation. This PhD project involves close collaboration and therefore international travel at the University of Southampton and the Weizmann Institute of Science.