Quantum Photonic Connections Conference - ABSTRACTS

Prof Terry Rudolph

Imperial College London, UK

Why I am Optimistic About Silicon-Photonic Quantum Computing

I will overview how CMOS compatible processes can build all necessary components for a quantum computer, and summarize the main architectural challenges with integrating them appropriately.

Prof Chao-Yang Lu

University of Science and Technology China

Creating perfect single photons for the demonstration of quantum supremacy

In this talk, I will report two routes towards experimental boson sampling with many photons.
One is based on spontaneousparametric down-converted (SPDC) photon pairs that are generated probabilistically. Exploiting scattershot boson sampling scheme, the probabilistic nature of SPDC can be overcome by using ~n^2 SPDC sources. The other, more direct, route is employing deterministically generated single photons from solid-state quantum emitters.

Prof Tim Ralph

University of Queensland, Brisbane

Enhancing quantum communication channels

We present experimental results in which a two-mode squeezed state that has been corrupted by passage through a lossy channel is recovered via distillation. The level of entanglement in our distilled state is higher than that achievable by direct transmission of any state through a similar loss channel. This is a key bench-marking step towards the realisation of a practical continuous-variable quantum repeater and other CV quantum protocols. I will discuss progress in developing such protocols.

Prof Ping Koy Lam

Australian National University, Canberra

Surpassing the no-cloning limit with hybrid probabilistic nonlinear amplifiers

An arbitrary quantum state cannot be amplified or cloned perfectly. The no-cloning theorem sets a limit to the fidelity of any clones produced by a deterministic linear amplifier. At the expense of determinism, we show that it is possible to approximate noiseless linear amplification. In this talk, we show experimental results that produce clones that have a fidelity surpassing the no-cloning limit with heralded successes. Our probabilistic amplifier allows us to clone up to five high fidelity copies of a single quantum state.

Dr Mirko Lobino

Griffith University, Brisbane

Quantum photonics with lithium niobate waveguide

Until recently, quantum photonic architecture comprised of large-scale (bulk) optical elements, leading to severe limitations in miniaturization, scalability and stability. Recently integrated quantum optical circuitry was demonstrated for several applications including quantum gates, quantum metrology and generation of single photons. The monolithic nature of these devices means that the correct phase can be stably realized in what would otherwise be an unstable interferometer, greatly simplifying the task of implementing sophisticated photonic quantum circuits. In this seminar I will report on use of the lithium niobate platform for quantum application. In particular on the use of nonlinear devices for the generation of nonclassical state and frequency conversion and electro-optical devices for single photon multiplexing.

A/Prof Matthew Sellars

Australian National University, Canberra

Creation and storage of non-classical states of light using spin-waves in rare-earth doped crystals

Quantum memories for light will be key elements in future quantum communication networks. Rare-earth optical centres in crystals, with their long optical and spin coherence times, are uniquely suited for this application. Quantum information stored on the rare-earth centres can be easily transferred between electronic states and nuclear spin states, enabling the long-term storage required for long range communications. Further, the high spatial density possible with these centres can be utilized to realise the large data storage densities required for high speed communications. This talk will cover the recent demonstration of the generation and storage of quantum entanglement in a rare-earth based spin-wave memory and progress in developing a spin-wave quantum memory operating in the 1550 nm communication band.