A5042526123- Quantum and electron transport phenomena
- Quantum optics and atomic interactions
- Semiconductor Quantum Structures and Devices
- Quantum Information and Cryptography
- Quantum Computing Algorithms and Architecture
- Atomic and Subatomic Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- Mechanical and Optical Resonators
- Quantum, superfluid, helium dynamics
- Advanced NMR Techniques and Applications
- Physics of Superconductivity and Magnetism
- Advancements in Semiconductor Devices and Circuit Design
- Laser-Matter Interactions and Applications
- Magnetic properties of thin films
- Diamond and Carbon-based Materials Research
- Quantum many-body systems
University of Cambridge
2019-2023
Coherent excitation of an ensemble quantum objects underpins many-body phenomena and offers the opportunity to realize a memory that stores information. Thus far, deterministic coherent interface between spin qubit such has remained elusive. In this study, we first used electron cool mesoscopic nuclear semiconductor dot sideband-resolved regime. We then implemented all-optical approach access individual quantized electronic-nuclear transitions. Lastly, performed optical rotations single...
Abstract Quantum control of solid-state spin qubits typically involves pulses in the microwave domain, drawing from well-developed toolbox magnetic resonance spectroscopy. Driving a by optical means offers high-speed alternative, which presence limited coherence makes it preferred approach for high-fidelity quantum control. Bringing full versatility to domain requires phase and amplitude fields. Here, we imprint programmable sequence onto laser field perform electron semiconductor dot via...
Purifying a high-temperature ensemble of quantum particles toward known state is key requirement to exploit many-body effects. An alternative passive cooling, which brings system its ground state, active feedback, stabilizes the at chosen target state. This alternative, if realized, offers additional control capabilities for design states. Here we present feedback algorithm applied system, capable stabilizing collective an from maximum entropy limit single fluctuations. Our algorithmic...
Combining highly coherent spin control with efficient light-matter coupling offers great opportunities for quantum communication and networks, as well computing. Optically active semiconductor dots have unparalleled photonic properties, but also modest coherence limited by their resident nuclei. Here, we demonstrate that eliminating strain inhomogeneity using lattice-matched GaAs-AlGaAs dot devices prolongs the electron nearly two orders of magnitude, beyond 0.113(3) ms. To do this, leverage...
We present a coherent quantum feedback algorithm to purify mesoscopic spin ensemble at the ultimate level of single spin. Applying it dot narrowed nuclear-spin fluctuations by two orders magnitude.
A resident electron spin in a semiconductor nanostructure is an interface to ensemble of nuclear spins, and witnesses the creation entanglement within form dark-state coherences.
Purifying a high-temperature ensemble of quantum particles towards known state is key requirement to exploit many-body effects. An alternative passive cooling, which brings system its ground state, based on feedback stabilise the actively around target state. This alternative, if realised, offers additional control capabilities for design states. Here we present algorithm capable stabilising collective an from infinite-temperature limit single quanta. We implement this ~50,000 nuclei in...
Taking full advantage of the outstanding optical properties self-assembled InGaAs quantum dots requires a highly sophisticated spin control technique. We develop and implement such technique for locking, protecting state much longer than inhomogeneous dephasing time.
We implement an all-optical access to the quantized electronic-nuclear spin transitions in a semiconductor quantum dot, and we perform coherent rotations of collective nuclear excitation corresponding spin-wave called magnon.
Coherent excitation of an ensemble quantum objects offers the opportunity to realise robust entanglement generation and information storage in a memory [1]. Thus far, interfacing with such collective deterministically has remained elusive owing difficulty controlling probe spin midst complex many-body system. In strained atomic lattice semiconductor dot, nuclear quadrupole effects generate electron-nuclear interaction that can be engineered by driving electron (Fig. 1a). By implementing...
We report on the firsts pin-control experiments in optically active GaAs/AlGaAs quantum dots. Using dynamic decoupling, we retain a superposition for up to 105 µ s, hundred-fold improvement over state-of-the-art.
We report on the first s pin-control e xperiments i n o ptically active GaAs/AlGaAs quantum dots. Using dynamic decoupling, we retain a superposition for up to 105 μ s, hundred-fold improvement over state-of-the-art.
We report on the first spin-control experiments in optically active GaAs/AlGaAs quantum dots. Using dynamic decoupling, we retain a superposition for up to 27 μ s, ten-fold improvement over state-of-the-art.
We present a coherent quantum feedback algorithm to purify mesoscopic spin ensemble at the ultimate level of single spin. Moreover our can engineer classically correlated states extending over multiple modes.