Photonic Quantum Technology
Photonic quantum technology exploits novel devices based on photons and encompasses the development of hardware for photonic quantum simulators, quantum networks, quantum cryptography, and novel light sources.
A main goal is to build commercially relevant quantum photonic circuits based on quantum dots in photonic nanostructures. This will serve as a basis of a “push-button” coherent single-photon source targeting applications for photonic quantum simulators or proof-of-concept quantum networks.
The development of the technology will be carried out in collaboration with, among others, Accelink Denmark, Elionix, ID Quantique, Montana Instruments, Toptica Photonics, Cryptomathic, Danish Institute of Fundamental Metrology, Attocube Systems, and Danfysik.
Quantum dot photon-emitter interfaces:
Photons are excellent carriers of quantum information that can be distributed over long distances through optical fibers. Quantum information can be easily encoded in, e.g., the propagation path or the time bin of a single photon, which is robust against decoherence.
A significant activity in Qubiz is to develop the full potential of quantum-dot photon-emitter interfaces leading to, e.g., deterministic single-photon sources. A main engineering challenge is to harvest many identical single photons from a single quantum-dot source providing a resource for quantum simulators and demonstrating quantum supremacy. It is predicted that only 40 photons may be a sufficient quantum resource to outperform existing supercomputers for certain tasks.
Photonic quantum simulators and quantum networks:
A large activity within Qubiz is to use the developed sources to demonstrate proof-of-concept quantum simulators with single photons. The simplest algorithms exploits single photons, quantum interference, and photon detection as the required resources. The development of low-loss photonic circuity including active single-photon switches is a main research topic, which eventually will determine how complex quantum algorithms that can be implemented. More advanced protocols will be exploited as well, where a large-scale entangled cluster state is generated directly from the quantum dot, and the quantum algorithm subsequently implemented by measurement. The long-term goal is to construct a quantum network of multiple stationary qubits (quantum dots) connected in a fully quantum manner by flying qubits (single photons).
Exploring distributed quantum resources:
As various approaches to quantum technology ripen, it becomes essential to set up an infrastructure for the distributed use of quantum hardware. Three main challenges will be addressed:
- programming of user interface for remote control of quantum components;
- active stabilization of the experimental apparatus, which will enable many hours of “hands off” continuous operation;
- developing the virtual marketplace, in which end users are presented to the facilities and contracts can be made.
Associate Professor at Quantum Photonics, Niels Bohr Institute (NBI)
Professor at Quantum Physics, Niels Bohr Institute (NBI)
Associate professor at Department of Physics and Astronomy, Aarhus University (AU)