Research Updates

September 2018

Nonreciprocal Transmission and Reflection of a Chirally Coupled Quantum Dot, Hurst et al

Nano Lett, 2018, 18(9), pp 5475-5481 published on 6 August 2018

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August 2018

High Purcell factor generation of indistinguishable on-chip single photons

On-chip single-photon sources are key components for integrated photonic quantum technologies. Semiconductor quantum dots can exhibit near-ideal single-photon emission, but this can be significantly degraded in on-chip geometries owing to nearby etched surfaces .....

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July 2018

Electrical control of nonlinear quantum optics in a nano-photonic waveguide

Quantum photonics is a rapidly developing platform for future quantum network applications. Waveguide-based architectures, in which embedded quantum emitters act as both nonlinear elements to mediate photon–photon interactions and as highly coherent single-photon sources, offer a highly promising route to realize such networks .....

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May 2018

Exciton Polaritons in a Two-Dimensional Lieb Lattice with Spin-Orbit Coupling

We study exciton polaritons in a two-dimensional Lieb lattice of micropillars. The energy spectrum of the system features two flat bands formed from S and Px;y photonic orbitals, into which we trigger bosonic condensation under high power excitation .....

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April 2018

Thin Al1-x GaxAs0.56Sb0.44 Diodes With Low Excess Noise

Thin avalanche layers have been adopted to achieve low excess noise and high-gain bandwidth products in InP and InAlAs avalanche photodiodes. In this paper, we report the excess noise characterization in a series of Al1-xGaxAs0.56 Sb0.44 (x = 0, 0.05, 0.1, 0.15) diodes with avalanche layer thickness of 110-116 nm .....

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March 2018

A quantum light-emitting diode for the standard telecom window around 1,550nm

Single photons and entangled photon pairs are a key resource of many quantum secure communication and quantum computation protocols, and non-Poissonian sources emitting in the low-loss wavelength region around 1,550nm are essential for the development of fibre-based quantum network infrastructure. However, reaching this wavelength window has been challenging for semiconductor-based quantum light sources .....

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January 2018

Hybrid gap plasmon GaAs nanolasers

Compact semiconductor lasers with sub-wavelength-scale dimensions rely heavily on materials with low surface recombination due to the large surface area to volume ratios of their nano-cavities. Furthermore, the reliance on semiconductor nanostructures has led to predominantly bottom-up fabrication approaches, which has hindered scalable and practical applications. In this letter, we present lithographically constructed hybrid gap plasmon nanolasers using the gain of bulk GaAs operating at room temperature .....

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January 2018

Tunable, CW Laser Emission at 225 nm via Intracavity Frequency Tripling in a Semiconductor Disk Laser

Numerous applications would benefit from a compact laser source with tunable, continuous-wave emission in the deep ultraviolet (wavelengths <;250 nm); however, very few laser sources have been demonstrated with direct emission in this spectral region and options are generally limited to pulsed, fixed wavelength sources or complex and impractical setups for nonlinear frequency mixing of the emission of several infrared lasers in various external enhancement cavities .....

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December 2017

Improving a Solid-State Qubit through an Engineered Mesoscopic Environment

A controlled quantum system can alter its environment by feedback, leading to reduced-entropy states of the environment and to improved system coherence .....

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December 2017

Transmission electron microscopy of AlGaAs/GaAs quantum cascade laser structures

Quantum cascade lasers can be efficient infrared radiation sources and consist of several hundreds of very thin layers arranged in stacks that are repeated periodically. Both the thicknesses of the individual layers as well as the period lengths need to be monitored to high precision .....

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