Project description
Next-generation single-photon source lights the way to scalable quantum computing
A promising approach for quantum computing is to use an optical architecture, in which qubits are represented by photons and manipulated by simple optical components. To date, researchers have demonstrated this method on a very small scale by performing operations using just a few single photons. To perform any kind of meaningful quantum information processing with these qubits, hundreds of photons are needed. As a result, single-photon sources are expected to produce on-demand single photons with high efficiency and near-unity indistinguishability, simultaneously. The EU-funded UNITY project will conduct groundbreaking research to build such a perfect single-photon source that overcomes the existing trade-off between high photon collection efficiency and photon indistinguishability, which presently hinders further progress in optical quantum information science.
Objective
Within optical quantum information processing, the quantum bits are encoded on single photons and their quantum mechanical properties are exploited to build new functionality. A prime example is the quantum computer, which can be built simply from single-photon sources and detectors, and simple optical components. However for scalable optical quantum computing involving hundreds of photons, the performance requirements for the single-photon source are daunting: the source must feature near-unity efficiency and near-unity indistinguishability simultaneously! Today, all known source designs suffer from inherent trade-offs between efficiency and indistinguishability and their performance is insufficient for scalable quantum computing.
The project objective is to realize a source of single indistinguishable photons with performance of ground-breaking nature. The break-through lies in the simultaneous realization of near-unity efficiency and indistinguishability, a combination which overcomes the limitations of present state-of-the-art and ventures far into the regime of scalable quantum computing.
As an expert in single-photon source engineering I find myself in a unique position to address this challenge. Since it is unknown how to design such a source, I will first establish a new understanding of the physics of the near-unity regime, where phonon-induced decoherence represents a main limitation for the indistinguishability. I will then advance state-of-the-art in optical engineering by proposing a novel design, where all physical parameters can be controlled independently. The modelling of the near-unity performance source is extremely demanding, and the analysis requires additional advances within optical simulations and open quantum systems theory. Once this is achieved, I will fabricate a prototype and test it in a multi-photon interference boson sampling experiment to unambiguously prove that scalable optical quantum information processing is indeed within reach.
Fields of science
Programme(s)
Funding Scheme
ERC-COG - Consolidator GrantHost institution
2800 Kongens Lyngby
Denmark