To build the quantum internet of the future we need two key devices: a bright source of high-quality single photons, and a quantum memory that can store and retrieve these photons. We are working towards interfacing these two key technologies for the first time, which represents a key building block towards scalable quantum networks.
Single-photon sources based on semiconductor quantum dots embedded in micropillar cavities have emerged as high-performance single-photon sources. Quantum memories based on light-matter interactions in warm atomic ensembles have been demonstrated to enable efficient, noise-free storage of high-bandwidth photons. Whilst these two technologies are independently well-established, they have not yet been interfaced due to incompatibilities in their operational wavelengths and bandwidths, and the challenge of working with two different physical platforms.
In this project we will interconnect these two key technologies by storing photons from a quantum dot single-photon source in an atomic quantum memory. In order to optimize the efficiency of the interface we will harness the temporal mode properties of the quantum memory to tailor the storage mode to match that of the photons, and explore methods to extend the maximum storage time of the memory. We will demonstrate that we can store a photon in the quantum memory and retrieve it at a later time with high efficiency. Furthermore we will demonstrate that the quantum memory acts as a coherent filter and improves the purity of the retrieved single photons. The interface of these two devices will represent a key building block towards scalable quantum networks.
This 3.5-year studentship is funded by the UKRI Quantum Computing and Simulations (QCS) hub and ORCA Computing. The project is based in the Photonic Quantum Information group at Imperial College London, and will be co-supervised by Prof Ian Walmsley and Dr Sarah Thomas. The Photonic Quantum Information group has a large well-equipped quantum memories lab with all of the necessary equipment including pulsed laser systems, low-vibration cryostat and single-photon detectors.
Academic entry requirements
Candidates should hold, or expect to receive, a First Class or good Upper Second Class Honours Degree (or the equivalent) in Physics or a related subject. A master’s level qualification would be advantageous.
How to apply:
Informal enquiries are welcomed and encouraged, and should be directed to Dr Sarah Thomas at [Email Address Removed]
Note: applications may close earlier than the advertised deadline (14th April) if a suitable candidate is found; therefore we recommend that you contact us prior to applying, and submit your formal application as early as possible.
Formal applications should be made via Imperial College London’s application page https://www.imperial.ac.uk/study/apply/postgraduate-doctoral/
Continue with Facebook
