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Michael E. Reimer
Institute for Quantum Computing and Department of Electrical and Computer Engineering,
University of Waterloo

Abstract

Quantum photonic devices are emerging from the lab toward real-world applications at an ever increasing pace. The applications range from the secure transfer of information for banking and communication, to quantum radar for national defense, assistance in search and rescue missions, to biomedical applications such as in dose monitoring for cancer treatment as well as in non-invasive imaging of the eye, to diagnose potentially blinding diseases. In these applications, new types of quantum photonic hardware are required including the cutting edge generation of entangled photon pairs and light detection at the single-photon level. In addition to these new types of quantum photonic hardware, manipulation of single photons on a chip is required for photonic quantum computing.

In my talk, I will discuss how we generate entangled photon pairs with semiconductor quantum dots in shaped nanowire waveguides [1, 2]. I will present our recent work towards engineering these sources to reach perfect entanglement with near-unity efficiency [3, 4, 5]. Currently, this is a feat not attainable with leading photon technologies based on parametric down-conversion due to the probabilistic nature of the generation process and self-assembled quantum dots due to dephasing processes and/or poor collection efficiency. I will also present how these quantum light sources can be integrated within a quantum photonic circuit on a silicon chip to route and filter single photons [6, 7].

Further to this, I will present our newest and most exciting work. We have developed a new type of quantum sensor that detects light over an unprecedented wavelength range, from the UV to near-infrared with high speed and timing resolution [8]. Lastly, I will illuminate how our nanostructure is uniquely shaped to achieve near-unity efficiency over the entire wavelength range, and show how we can extend the wavelength detection range to the infrared and beyond in the future, to continue changing the future of quantum photonic devices from the lab to the real world.

References

[1] M.A.M. Versteegh et al., Observation of strongly entangled photon pairs from a nanowire quantum dot, Nature Commun. 5, 5298 (2014).

[2] K.D. Jöns et al., Bright nanoscale source of deterministic entangled photon pairs violating Bell’s inequality, Scientific Reports 7, 1700 (2017).

[3] A. Fognini et al., Dephasing free photon entanglement with a quantum dot, ACS Photonics 6 (7), 1656-1663 (2019).

[4] A. Fognini et al., Universal fine-structure eraser for quantum dots, Optics Express 26 (19), 24487-22496 (2018).

[5] M. Zeeshan et al., Proposed scheme to generate bright entangled photon pairs by application of a quadrupole field to a single quantum dot, Phys. Rev. Lett. 122, 227401 (2019).

[6] I.E. Zadeh et al., Deterministic integration of single photon sources in silicon based photonic circuits, Nano Lett. 16 (4), 2289-2294 (2016).

[7] A. Elshaari et al., On-chip single photon filtering and multiplexing in hybrid quantum photonic circuits, Nature Commun. 8, 379 (2017).

[8] S. Gibson et al., Nature Nanotechnology 14 (5), 473 (2019).

Zoom Link:

Email:  will.salmon@queensu.ca for zoom link.