Dr Jonathan Pritchard

Research Fellow


Personal statement

Jonathan Pritchard recieved his PhD from Durham University in 2011, studying cooperative optical non-linearities at the single photon level arising from strong atomic interactions. He then joined the Photonics group at the University of Strathclyde building a new apparatus for atom interferometry with a Bose-Einstein Condensate for inertial sensing. He then joined the hybrid quantum information group at the Univeristy of Wisconsin-Madison in 2013, developing a new project to trap a single atom close to a superconducting circuit for a hybrid quantum memory. Jonathan was recently awared an EPSRC Quantum Technology Fellowship in July 2015 to start a new project at the University of Strathclyde using hybrid atom-superconductor devices to develop next generation hardware for quantum networking.


Optimized coplanar waveguide resonators for a superconductor-atom interface
Beck M A, Isaacs J A, Booth D, Pritchard J D, Saffman M, McDermott R
Applied Physics Letters Vol 109 (2016)
Long working distance objective lenses for single atom trapping and imaging
Pritchard JD, Isaacs JA, Saffman M
Review of Scientific Instruments Vol 87 (2016)
Measurement of holmium Rydberg series through magneto-optical trap depletion spectroscopy
Hostetter J, Pritchard J D, Lawler J E, Saffman M
Physical Review A Vol 91 (2015)
Microwave control of the interaction between two optical photons
Maxwell D, Szwer D J, Paredes-Barato D, Busche H, Pritchard J D, Gauguet A, Jones M P A, Adams C S
Physical Review A Vol 89 (2014)
Hybrid atom-photon quantum gate in a superconducting microwave resonator
Pritchard J D, Isaacs J A, Beck M A, McDermott R, Saffman M
Physical Review A Vol 89 (2014)
Storage and control of optical photons using Rydberg polaritons
Maxwell D, Szwer D J, Paredes-Barato D, Busche H, Pritchard J D, Gauguet A, Weatherill K J, Jones M P A, Adams C S
Physical Review Letters Vol 110 (2013)

more publications

Research interests

Hybrid quantum technologies, atomic physics, quantum optics, single photon non-linearities

Professional activities

Towards scalable quantum computing with neutral atoms
Intelligent Computational Engineering quantum computing event
Invited speaker
Quantum Technology Showcase 2019
Scottish Centre for Innovation in Quantum Computing and Simulation Industry Workshop
Rydberg atom quantum information
External PhD Examination, UCL

more professional activities


Scalable Qubit Arrays for Quantum Computation and Optimisation (M Squared Prosperity Partnership)
Pritchard, Jonathan (Principal Investigator) Daley, Andrew (Co-investigator) Riis, Erling (Co-investigator)
05-Jan-2020 - 04-Jan-2025
Microwave and Terahertz Field Metrology and Imaging using Rydberg Atoms
Pritchard, Jonathan (Principal Investigator)
01-Jan-2019 - 28-Jan-2022
UCL CDT Studentship L Keary
Pritchard, Jonathan (Principal Investigator)
01-Jan-2018 - 30-Jan-2021
QuDOS II: Quantum technologies using Diffractive Optical Structures (Phase II)
Griffin, Paul (Principal Investigator) Arnold, Aidan (Co-investigator) Pritchard, Jonathan (Co-investigator)
01-Jan-2017 - 28-Jan-2018
Quantum technologies using Diffractive Optical Structures (Phase II)
Griffin, Paul (Principal Investigator) Arnold, Aidan (Co-investigator) Pritchard, Jonathan (Co-investigator)
01-Jan-2017 - 01-Jan-2018
A Hybrid Atom-Photon-Superconductor Quantum Interface
Pritchard, Jonathan (Fellow)
"The field of quantum information arises from a desire to overcome the challenges of solving complex or intractable problems on classical computers by harnessing quantum mechanics to provide efficient and scalable algorithms. Whilst there has been tremendous recent progress in the realisation of small-scale quantum circuits comprising several quantum bits ("qubits''), research indicates that a fault-tolerant quantum computer capable of harnessing the power of quantum mechanics will require a network of thousands of qubits. This goal is presently beyond the reach of any existing implementation based on a single physical qubit type.

Hybrid quantum information processing is an alternative approach that exploits the unique strengths of disparate quantum technologies, and offers a route to overcome the drawbacks associated with of a single-qubit architecture in direct analogy to the design of classical computing hardware. This proposal aims to combine three different technologies:

i) Superconducting circuits, with very fast (10 ns) gate times for fast processing,
ii) Neutral atoms, with long (10 s) coherence times for long lived quantum memory,
iii) Optical photons, for long distance fibre communication,

to create a novel hybrid quantum interface capable of storing, processing and generating highly entangled states of photons for quantum networking and cryptography applications, overcoming the short coherence time associated with the scalable superconducting circuit systems. This also offers applications in quantum metrology for conversion from optical to microwave domain quantum information, making it possible to extend the interface to incorporate a wide range of alternative solid-state based qubits.

The interface relies on use of highly excited Rydberg states, which have incredibly large dipole moments and transitions in the microwave regime, which can resonantly couple to superconducting qubits embedded in planar microwave waveguide cavities. The large Rydberg dipole also leads to strong, controllable interactions between atoms to provide a collective enhancement in the coupling to single photons for efficient storage and retrieval of light.

The first stage of the experiment is to trap spatially addressable atomic ensembles above a superconducting microwave resonator operating at 4 K to demonstrate strong coupling to the waveguide mode, a key milestone for implementing the hybrid interface. The ensembles will then be utilised to perform coherent storage and retrieval of optical photons, as well as generation of single photons using four-wave mixing.

The second stage is to exploit the off-resonant interaction with the cavity to achieve controllable long distance (~1 cm) entanglement between a pair of ensembles trapped within a single microwave resonator. This will then be used to generate entangled photon pairs, exploring the benefits of collective encoding within the ensembles for achieving entanglement in the polarisation degrees of freedom for long-distance cryptographic quantum key distribution. The resulting hybrid quantum interface provides an ideal building block for establishing quantum networks. Long term this can be integrated with existing superconducting qubit technologies, making a significant step towards the realisation of scalable quantum computing."
01-Jan-2015 - 30-Jan-2020

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