Solid State Superatoms

Lead Research Organisation: Durham University
Department Name: Physics

Abstract

The modern digital world relies on classical two-level systems - binary bits. A major theme of current physics research is the development of their quantum equivalent "qubits" - isolated two-level quantum systems, for applications in computing, sensing, measurement and communication. A logical quantum bit may be encoded using the physical states of an ensemble of many individual atoms. A powerful way to carry out such a collective encoding is to exploit highly excited electronic states, known as Rydberg states that have strong long-range interactions with neighbouring atoms. So far, this method has been demonstrated in a laser-cooled atomic gas, but not in the solid state.

We propose to use atom-like electronic states known as excitons, in a semiconducting signal. Excitons couple to light and can be excited to a Rydberg state, where their wavefunction can encapsulate billions of lattice sites. Using methods from solid state physics (strain engineering) and atomic physics (microwave control), we aim to isolate collective solid state two-level systems (superatoms), and prove their existence using the quantum properties of the light they emit. Finally we plan to exploit the translational symmetry of the bulk crystal environment to create tailored arrays of superatoms.

Planned Impact

Short term: The primary beneficiary of the proposed work is the UK Quantum technology community (scientists, engineers and companies), in the following ways:
-People: The project will directly train two PDRAs in the cutting-edge skills needed in the quantum technology arena, and provide a training opportunity for at least two graduate students, as well as undergraduates.
-Knowledge: We open up a new research direction in the solid state that exploits atom-like highly excited states, with applications that include quantum optics and quantum interfaces. The proposal combines methods from solid state and atomic physics, with impact in both. We plan to use this project link these communities more closely.

Medium and long term: Economic impact could result in the medium to long term, through applications of the proposed research to sources of non-classical light and interfaces to superconducting quantum circuits such as those used in the first commercial quantum computer (D-Wave).

Publications

10 25 50
 
Description CASE studentship with DSTL 
Organisation Defence Science & Technology Laboratory (DSTL)
Country United Kingdom 
Sector Public 
PI Contribution Working with DSTL exploring microwave sensing with excitons in cuprous oxide
Collaborator Contribution Partner for industrial CASE - stipend enhancement and hosting of placement
Impact N/A
Start Year 2017
 
Description Celebrate Science 2019 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Celebrate Science is an annual science festival aimed at school children held in Durham in the October half term. It is well established, and attended by >1000 people over typically four days.
Staff employed on this project contributed to an activity on optics (polarization) and spectroscopy
Year(s) Of Engagement Activity 2019
URL https://www.dur.ac.uk/celebrate.science/