A5078251894- Photonic and Optical Devices
- Photonic Crystals and Applications
- Quantum optics and atomic interactions
- Quantum Information and Cryptography
- Semiconductor Lasers and Optical Devices
- Mechanical and Optical Resonators
- Neural Networks and Reservoir Computing
- Plasmonic and Surface Plasmon Research
- Quantum Mechanics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Emergency and Acute Care Studies
- Trauma and Emergency Care Studies
- Injury Epidemiology and Prevention
- Nonlinear Dynamics and Pattern Formation
- Topological Materials and Phenomena
- Laser-Matter Interactions and Applications
- Crystallography and Radiation Phenomena
- Heat shock proteins research
- Optical Coatings and Gratings
- Advanced Optical Network Technologies
- Orbital Angular Momentum in Optics
- Computational Drug Discovery Methods
- Random lasers and scattering media
- Electromagnetic Scattering and Analysis
- Quantum and Classical Electrodynamics
University of Nottingham
2020-2025
Applied Radar (United States)
2023
University of Bristol
2014-2022
Bristol Robotics Laboratory
2015-2022
Beth Israel Deaconess Medical Center
2017
Harvard University
2017
<h3>Importance</h3> The National Pediatric Readiness Project is a US initiative to improve emergency department (ED) readiness care for acutely ill and injured children. However, it unclear whether high ED pediatric associated with improved survival in trauma centers. <h3>Objective</h3> To evaluate the association between readiness, in-hospital mortality, complications among children presenting <h3>Design, Setting, Participants</h3> A retrospective cohort study of 832 EDs centers 50 states...
<h3>Importance</h3> There is substantial variability among emergency departments (EDs) in their readiness to care for acutely ill and injured children, including US trauma centers. While high ED pediatric associated with improved in-hospital survival children treated at centers, the association between long-term outcomes unknown. <h3>Objective</h3> To evaluate 1-year presenting 146 <h3>Design, Setting, Participants</h3> In this retrospective cohort study, younger than 18 years who were...
Semiconductor quantum dots in photonic crystal waveguides are building blocks for technology. Placing the at locations where waveguide modes have circular polarization enables light emission only one direction with a high probability of coupling to mode, beta factor. The authors use spectral imaging determine factor and directionality, doing away assumptions on rates into nonguided modes. In fast-light regime, they find coupling, close unity, quantum-dot position inside waveguide.
Emitter ensembles interact collectively with the radiation field. In case of a one-dimensional array atoms near nanofiber, this collective light-matter interaction does not only lead to an increased photon coupling guided modes within fiber, but also drastic enhancement chirality in emission. We show that near-perfect can be achieved already for moderately sized ensembles, containing 10 15 atoms, by phase matching superradiant emission mode via external laser This is importance developing...
Recently we introduced a local photon approach for modeling the quantized electromagnetic field in position space. Using this approach, define momentum of light paper as quantum mechanics generator spatial translation. Afterward, analyze dynamics photonic wave packets which transition from air into denser dielectric medium. Our analysis shines new onto Abraham-Minkowski controversy, highlights intricacies involved characterization field. Although our results align with Minkowski's theory and...
Unidirectional (chiral) emission of light from a circular dipole emitter into waveguide is only possible at points perfect polarization (C points), with elliptical polarizations yielding lower directional contrast. However, there no need to restrict engineered systems dipoles, and an appropriate choice unidirectional for any polarization. Using rather than circular, typically increases the size area suitable chiral interactions (in exemplary mode by factor ∼30), while simultaneously...
We investigate the conditions under which a set of multipartite nonlocal correlations can describe distributions achievable by distant parties conducting experiments in consistent universe. Several questions are posed, such as: all sets 'nested', i.e., contained into one another? Are they discrete or do form continuum? How many them supraquantum? there non-trivial polytopes among them? answer some these relate to established conjectures complexity theory introducing 'zoo' physically sets, be...
We explore the dissipative dynamics of nonlinearly driven oscillator systems tuned to resonances where multiple excitations are generated. Such readily realised in circuit QED combining Josephson junctions with a microwave cavity and drive achieved either through flux or voltage bias. For involving 3 more photons system undergoes sequence two closely spaced dynamical transitions (the first one discontinuous second continuous) as driving is increased leading steady states that form complex...
The effects of short-range disorder on the polarization characteristics light in photonic crystal waveguides were investigated using finite-difference time-domain simulations with a view to investigating stability singularities. It was found that points local circular ($C$ points) and contours linear ($L$ lines) continued appear even presence high levels disorder, they remained close their positions ordered crystal. These results are promising indication devices exploiting these structures...
Photonic crystal waveguides are known to support C-points - point-like polarisation singularities with local chirality. Such points can couple dipole-like emitters produce highly directional emission, from which spin-photon entanglers be built. Much is made of the promise using slow-light modes enhance this light-matter coupling. Here we explore transition travelling standing waves for two different photonic waveguide designs. We find that time-reversal symmetry and reciprocal nature light...
We present slow-light photonic crystal waveguide designs that provide a $\times$8.6 improvement of the local density optical states at fully chiral point over previous designs.
A Josephson junction laser is realised when a microwave cavity driven by voltage-biased junction. Through the ac effect, dc voltage generates periodic drive that acts on and interactions between its modes. sufficiently strong enables processes down-convert resonant with high harmonic into photons at fundamental frequency, breaking discrete time translation symmetry set frequency. Using classical model, we determine how this transition occurs as function of bias number We find certain...
A unidirectional chiral edge mode in photonic topological insulators can be selectively excited by a circularly-polarized dipole source. We show that the directionality is also determined position of
Bell's theorem shows that no local hidden-variable model can explain the measurement statistics of a quantum system shared between two parties, thus ruling out classical (local) understanding nature. In this paper we demonstrate by relaxing positivity restriction in probability distribution it is possible to derive quasiprobabilistic Bell inequalities whose sharp upper bound written terms negativity witness said distribution. This provides an analytic solution for amount necessary violate...
Recently we introduced a local photon approach for modelling the quantised electromagnetic field in position space. Using this approach, paper define momentum of light, analogy to quantum mechanical point particles, as generator spatial translation photonic wave packets. Afterwards, analyse dynamics light when transitioning from air into denser dielectric medium. Our analysis shines new onto Abraham-Minkowski controversy which highlights intricacies involved characterisation field. Although...
We analyse the entanglement in a model Josephson photonics system which dc voltage-biased junction couples collection of cavity modes and populates them with microwave photons. Using an approximate quadratic Hamiltonian model, we study Gaussian that develops between as energy is increased. find fall into series blocks, bipartite generated within given block. Tripartite block also widespread, though it limited to certain ranges energy. The could provide alternative route generating multimode...
Rapid design tools are invaluable for the fast exploration of space and optimisation Photonic Crystal Surface Emitting Lasers (PCSELs). This paper introduces an improved extension to Effective Index type approach compares it against a large number numerical methods simulating PCSELS. These include two varieties effective-index method, coupled mode theory, guided expansion iterated method we here derive. All compared one another results obtained using 3D time domain solver where possible,...
Rapid design tools are invaluable for the fast exploration of space and optimisation Photonic Crystal Surface Emitting Lasers (PCSELs). This paper introduces an improved extension to Effective Index type approach compares it against a large number numerical methods simulating PCSELS. These include two varieties effective-index method, coupled mode theory, guided expansion iterated method we here derive. All compared one another results obtained using 3D time domain solver where possible,...
Rapid design tools are invaluable for the fast exploration of space and optimisation Photonic Crystal Surface Emitting Lasers (PCSELs). This paper introduces an improved extension to Effective Index type approach compares it against a large number numerical methods simulating PCSELS. These include two varieties effective-index method, coupled mode theory, guided expansion iterated method we here derive. All compared one another results obtained using 3D time domain solver where possible,...
We analyze the entanglement in a model Josephson photonics system which dc voltage-biased junction couples collection of cavity modes and populates them with microwave photons. Using an approximate quadratic Hamiltonian model, we study Gaussian that develops between as energy is increased. find fall into series blocks, bipartite generated within given block. Tripartite block also widespread, though it limited to certain ranges energy. The could provide alternative route generating multimode...
Inelastic Cooper pair tunneling across a voltage-biased Josephson junction in series with one or more microwave cavities can generate photons via resonant processes which the energy lost by matches that of photon(s) produced. We generalise previous theoretical treatments such systems to analyse cases where two different photon generation are simultaneously. also explore detail specific case single cavity mode is simultaneously second mode. find coexistence resonances leads effective...
Photonic crystal waveguides support chiral-point polarisation singularities which give rise to local chirality even in the absence of a global chiral symmetry. Placing quantum dot at such C-point gives uni-directional emission dependent on electron spin - ideal for applications information as it entangles direction electrons (static qubits) path waveguide (flying qubits). Here we discuss optimisation this light-matter interaction using slow-light waveguides, and show designs with 8.6 times...