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Dr BEN LANG's Outputs (15)

Assessment and Extension of Rapid Design Tools for Modelling Photonic Crystal Surface Emitting Lasers (2025)
Journal Article
Lang, B., Sewell, P., Vukovic, A., Boylan, K., Rihani, S., Moodie, D., Spalding, R., Hattasan, N., & Berry, G. (2025). Assessment and Extension of Rapid Design Tools for Modelling Photonic Crystal Surface Emitting Lasers. Journal of the Optical Society of America B, 42(5), 1123-1130. https://doi.org/10.1364/josab.550022

Rapid design tools are invaluable for the fast exploration of design space and optimization of photonic crystal surface-emitting lasers (PCSELs). This paper introduces an improved extension to the fast effective index type approach and compares it ag... Read More about Assessment and Extension of Rapid Design Tools for Modelling Photonic Crystal Surface Emitting Lasers.

Local-photon model of the momentum of light (2025)
Journal Article
Waite, G., Hodgson, D., Lang, B., Alapatt, V., & Beige, A. (2025). Local-photon model of the momentum of light. Physical Review A, 111(2), Article 023703. https://doi.org/10.1103/physreva.111.023703

Recently we introduced a local photon approach for modeling the quantized electromagnetic field in position space. Using this approach, we define the momentum of light in this paper as in quantum mechanics as the generator for spatial translation. Af... Read More about Local-photon model of the momentum of light.

Multipartite entanglement in a Josephson junction laser (2024)
Journal Article
Lang, B., & Armour, A. D. (2024). Multipartite entanglement in a Josephson junction laser. Physical Review A, 110(6), Article 062611. https://doi.org/10.1103/PhysRevA.110.062611

We analyze the entanglement in a model Josephson photonics system in which a dc voltage-biased Josephson junction couples a collection of cavity modes and populates them with microwave photons. Using an approximate quadratic Hamiltonian model, we stu... Read More about Multipartite entanglement in a Josephson junction laser.

Reflection by two level system: phase singularities on the Poincaré hypersphere (2023)
Journal Article
Lang, B., Harbord, E., & Oulton, R. (2023). Reflection by two level system: phase singularities on the Poincaré hypersphere. Journal of Optics, 25(12), Article 125403. https://doi.org/10.1088/2040-8986/ad065a

We consider the reflection of a photon by a two-level system in a quasi-one-dimensional waveguide. The waveguide polarisation at the location of the two-level system and the transition dipole are key determinants of the physics, controlling of the ph... Read More about Reflection by two level system: phase singularities on the Poincaré hypersphere.

Discrete time translation symmetry breaking in a Josephson junction laser (2023)
Journal Article
Lang, B., Morley, G. F., & Armour, A. D. (2023). Discrete time translation symmetry breaking in a Josephson junction laser. Physical review B: Condensed matter and materials physics, 107(14), Article 144509. https://doi.org/10.1103/PhysRevB.107.144509

A Josephson junction laser is realized when a microwave cavity is driven by a voltage-biased Josephson junction. Through the ac Josephson effect, a dc voltage generates a periodic drive that acts on the cavity and generates interactions between its m... Read More about Discrete time translation symmetry breaking in a Josephson junction laser.

Witnessing Bell violations through probabilistic negativity (2022)
Journal Article
Morris, B., Fiderer, L. J., Lang, B., & Goldwater, D. (2022). Witnessing Bell violations through probabilistic negativity. Physical Review A, 105(3), Article 032202. https://doi.org/10.1103/physreva.105.032202

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 a classical (local) understanding of nature. In this paper we demonstrate that by relaxing... Read More about Witnessing Bell violations through probabilistic negativity.

Perfect Chirality with Imperfect Polarization (2022)
Journal Article
Lang, B., McCutcheon, D. P., Harbord, E., Young, A. B., & Oulton, R. (2022). Perfect Chirality with Imperfect Polarization. Physical Review Letters, 128(7), Article 073602. https://doi.org/10.1103/physrevlett.128.073602

Unidirectional (chiral) emission of light from a circular dipole emitter into a waveguide is only possible at points of perfect circular polarization (C points), with elliptical polarizations yielding a lower directional contrast. However, there is n... Read More about Perfect Chirality with Imperfect Polarization.

Josephson photonics with simultaneous resonances (2021)
Journal Article
Wood, K., Armour, A. D., & Lang, B. (2021). Josephson photonics with simultaneous resonances. Physical Review B, 104(15), Article 155424. https://doi.org/10.1103/physrevb.104.155424

Inelastic Cooper pair tunneling across a voltage-biased Josephson junction in series with one or more microwave cavities can generate photons via resonant processes in which the energy lost by the Cooper pair matches that of the photon(s) produced. W... Read More about Josephson photonics with simultaneous resonances.

Multi-Photon Resonances in Josephson Junction-Cavity Circuits (2021)
Journal Article
Lang, B., & Armour, A. (2021). Multi-Photon Resonances in Josephson Junction-Cavity Circuits. New Journal of Physics, 23(3), Article 033021. https://doi.org/10.1088/1367-2630/abe483

We explore the dissipative dynamics of nonlinearly driven oscillator systems tuned to resonances where multiple excitations are generated. Such systems are readily realised in circuit QED systems combining Josephson junctions with a microwave cavity... Read More about Multi-Photon Resonances in Josephson Junction-Cavity Circuits.

Collectively enhanced chiral photon emission from an atomic array near a nanofiber (2020)
Journal Article
Jones, R., Buonaiuto, G., Lang, B., Lesanovsky, I., & Olmos, B. (2020). Collectively enhanced chiral photon emission from an atomic array near a nanofiber. Physical Review Letters, 124(9), Article 093601. https://doi.org/10.1103/physrevlett.124.093601

Emitter ensembles interact collectively with the radiation field. In the case of a one-dimensional array of atoms near a nanofiber, this collective light-matter interaction does not only lead to an increased photon coupling to the guided modes within... Read More about Collectively enhanced chiral photon emission from an atomic array near a nanofiber.

99% beta factor and directional coupling of quantum dots to fast light in photonic crystal waveguides determined by spectral imaging (2019)
Journal Article
Scarpelli, L., Lang, B., Masia, F., Beggs, D. M., Muljarov, E. A., Young, A. B., Oulton, R., Kamp, M., Höfling, S., Schneider, C., & Langbein, W. (2019). 99% beta factor and directional coupling of quantum dots to fast light in photonic crystal waveguides determined by spectral imaging. Physical Review B, 100(3), Article 035311. https://doi.org/10.1103/PhysRevB.100.035311

© 2019 American Physical Society. Spontaneous emission from excitonic transitions in InAs/GaAs quantum dots embedded in photonic crystal waveguides at 5 K into nonguided and guided modes is determined by direct spectral imaging. This enables measurem... Read More about 99% beta factor and directional coupling of quantum dots to fast light in photonic crystal waveguides determined by spectral imaging.

Time-reversal constraint limits unidirectional photon emission in slow-light photonic crystals (2016)
Journal Article
Lang, B., Beggs, D. M., & Oulton, R. (2016). Time-reversal constraint limits unidirectional photon emission in slow-light photonic crystals. Philosophical Transactions A: Mathematical, Physical and Engineering Sciences, 374(2075), https://doi.org/10.1098/rsta.2015.0263

Photonic crystal waveguides are known to support C-points—point-like polarization singularities with local chirality. Such points can couple with dipole-like emitters to produce highly directional emission, from which spin-photon entanglers can be bu... Read More about Time-reversal constraint limits unidirectional photon emission in slow-light photonic crystals.

Stability of polarization singularities in disordered photonic crystal waveguides (2015)
Journal Article
Lang, B., Beggs, D. M., Young, A. B., Rarity, J. G., & Oulton, R. (2015). Stability of polarization singularities in disordered photonic crystal waveguides. Physical Review A, 92(6), Article 063819. https://doi.org/10.1103/physreva.92.063819

The effects of short-range disorder on the polarization characteristics of light in photonic crystal waveguides were investigated using finite-difference time-domain simulations with a view to investigating the stability of polarization singularities... Read More about Stability of polarization singularities in disordered photonic crystal waveguides.

Closed sets of correlations: answers from the zoo (2014)
Journal Article
Lang, B., Vértesi, T., & Navascués, M. (2014). Closed sets of correlations: answers from the zoo. Journal of Physics A: Mathematical and Theoretical, 47(42), Article 424029. https://doi.org/10.1088/1751-8113/47/42/424029

We investigate the conditions under which a set of multipartite nonlocal correlations can describe the distributions achievable by distant parties conducting experiments in a consistent universe. Several questions are posed, such as: are all such set... Read More about Closed sets of correlations: answers from the zoo.