Postdoctoral Researcher Integrated Quantum Photonics

Be a frontrunner in enabling medium-to-large scale quantum photonics applications by enhancing imec s integrated photonics platforms

Quantum photonics is proposed as a vital, enabling technology for such disruptive concepts as an unbreakable quantum internet [1], and, more realistically, distributed sensor networks [2,3] and quantum enhanced sensing protocols [4]. For quantum photonics to progress from lab-based, proof-of-principle experiments to real life applications, aspects of integration (for scale-up, as well as realistic levels of control in non-lab environments) will need to be tackled. In some sense, this mimics evolutions in classical photonics, where integration has led to major breakthroughs in the past two decades. While photonics benefits from an inherent quantum protection against noise by virtue of the energy scales involved (eV photons, meV noise), the difficulty of making photons to interact and to store them also limit the scope several quantum applications.

At imec, we offer some of the best integrated photonics technology suites in the world, both in the visible (SiN based) and NIR/telecoms regime (Si photonics). In this postdoc, you will investigate and develop some of the missing links in our photonics portfolio to make it fully compatible with quantum applications. You will be embedded in several ongoing collaborative quantum photonics projects that have an innate need for *integrated* quantum photonics:

• Memoryless quantum repeaters: to distribute (entangled) quantum states in a lossy environment, dedicated machinery is needed to accommodate the losses and enhance the likelihood of success. One approach, which has been the subject of two decades of research, is a form of buffering involving quantum memories which in itself is non-trivial and opens the system up to noise. Alternatively, forms of redundancy can be used in combination with fast quantum switches and buffering to reroute the information on the fly: the so-called memoryless repeater [5,6]. Imec has, in principle, the necessary technologies available for such an approach, and is embedded in several project proposals in this space, ensuring the necessary links to be successful. However, demonstrating full capability is non-trivial, and you will be expected to contributed significantly to this task
• Linear optics quantum circuits [7]: the combination of linear optical elements such as interferometers, beamsplitters and number-resolving detectors, on chip, with weak (quantum) light sources allows for elementary quantum processors to be realized. Such small-scale processors can be used for on-chip quantum sensing and certain forms of key distribution. Also, in principle, they can be scaled up to much larger dimensions. Imec has some of the best, classical, integrated photonics platforms, yet in order to push the frontier of quantum photonics, different specs and characteristics need to be obtained. You will help identifying these missing links, design improved photonic quantum circuits and will be in charge of setting up novel measurement methodologies to characterize them.In addition, you will act as interface to the integration teams and guide them in developing new building blocks,