Summary
Individual atoms can act as stationary qubits and thus serve as nodes in quantum computing networks or as memories for quantum repeaters. However, to successfully use qubits based on single atoms suspended in free space, photons emitted by a single atom need to be efficiently collected. Conventionally, this can be done with high numerical aperture lenses, which can collect light from a large solid angle. Alternatively, placing the atom into a high-finesse cavity or within a sub-wavelength distance from the surface of a nano-photonic structure can affect the spatial pattern in which the atom emits photons and make the photon collection more efficient. However, these approaches remain experimentally challenging and can limit the potential for realistic scalability.
This project aims to achieve a distinctly novel way to control the emission pattern of a single atom by placing the atom at a distance of a few wavelengths from a chiral metasurface — a phased two-dimensional array of nano-scale metallic antennas or dielectric scatterers. We design and fabricate bi- and multi-layer structures with properly tuned interference between the radiation patterns of the layers. In the vicinity of such structures, the atom will emit light into a single, well defined direction without the need to place the atom at a sub-wavelength distance from a metallic or dielectric surface. The unidirectionally emitted photons can be efficiently coupled into optical fibers. Relative to current state-of-the-art, this platform simplifies and enables speed-up for certain quantum information processing tasks, such as remote entanglement between two distant atoms.
Simultaneously we will explore – through design and fabrication – the use of chiral metasurfaces for photon extraction from solid-state quantum emitters, such as colour centers in diamond. Here we hope to achieve increased photon collection efficiency from materials with high refractive index, which holds promise for improving the performance (speed and sensitivity) of electric and magnetic field sensors.
Related Content
Functionalized Nanodiamonds for Sensing Biochemical Processes
Summary Chemotherapy is limited by the failure to clinically monitor the efficacy of the treatment in real-time, which results in suboptimal chemotherapy being given for a prolonged period. Predicting the outcome of chemotherapy immediately after drug administration can increase diagnostic accuracy, efficacy outcomes, and successful treatment. Quantum nanodiamond sensors can be used as optical sensors […]
August 31, 2022
A Reformulation of Quantum Game Theory
Summary Classical game theory – conducted at the interface between economics and computer science – has found applications in topics ranging from networking and security to online markets. Despite over 20 years of research into connections between game theory and quantum information, we have yet to see any significant implications of quantum information when applied […]
April 1, 2020
Metasurfaces for high-efficiency parametric downconversion and complex quantum state generation
Summary Entangled photon sources are crucial for quantum computing, quantum sensing, and quantum communication. Of growing importance are sources relying on spontaneous parametric downconversion (SPDC). Unfortunately, these sources of entangled photons are often constrained by momentum conservation laws. To overcome this limitation and expand the possibility of quantum state engineering, we intend to use metasurfaces […]
February 1, 2023
Engineering and Characterizing Programmable Interaction Graphs in a Trapped Ion Quantum Simulator
Summary Quantum simulators have the potential to bring unprecedented capabilities in areas such as the discovery of new materials and drugs. Engineering precise and programmable interaction graphs between qubits or spins forms the backbone of simulator applications. The trapped ion system is unique in that the interaction graph between qubits can be programmed, in […]
July 24, 2018