An essential aspect of a quantum channel is the detection and analysis of quantum signals in the form of photons. For most free-space applications, the photons are polarization encoded, e.g. by assigning the ‘0’ to horizontally polarized photons and ‘1’ to vertically polarized photons. However, where the geometric reference is not constant at all times – such as links to hand-held devices or aircraft – polarization encoding leads to increased error. For these situations, time-bin encoding offers a promising robust solution. In this approach, time photon represents ‘0’ or ‘1’ depending on its detection in one of two time windows. Just like in the case of polarization encoding, where a photon can be in a superposition of vertical and horizontal polarization, a time-bin encoded photon can be in a superposition of being in the first and the second time window. Additionaly, quantum signals can be relatively easily converted between being polarization and time-bin encoded.
In this project, we jointly develop a quantum receiver with short time delay and high timing resolution that is optimized to handle time-bin encoded quantum signals. By combining our team’s expertise in free-space quantum receivers with a new detector array technology developed by Dr. Serge Charlebois and Jean-Francois Pratte of the University of Sherbrooke and by introducing new capabilities for integrated free-space time-bin encoding with high timing resolution detection, we expect to achieve state-of-the-art performance for quantum signal receiver technology. Such high-speed devices will open new doors for a variety of applications including daylight and continuous variable quantum key distribution, quantum sensing, imaging and LIDAR, and fundamental science tests.
Quantum Dynamics of Cavity Interactions with Spin Ensembles
Summary High quality factor cavities can be powerful control elements for ensembles of spins, enabling unitary control as well as on demand cooling. They can also be used to couple two otherwise non-interacting ensembles. The goal of the project is to explore the physics and engineering of such systems both theoretically and experimentally. The laboratory contains a […]
September 7, 2016
Advanced microwave electronics enabling quantum technologies
Summary Superconducting quantum computers require quantum-limited measurements at microwave frequencies in order to implement error correction. Conventionally, this is accomplished using near quantum-limited Josephson Parametric Amplifiers (JPAs). The JPAs require bulky ferrite-based circulators that prevent on-chip integration of the amplifiers with the processor and take up the majority of space and cooling power in the […]
April 1, 2020
Free-space Polarization-selective Microcavity based on Chiral Metasurfaces
Summary Developing a new type of Fabry-Pérot cavity that allows improved control of the atoms’ emission into the cavity mode will result in enhancement of the efficiency and fidelity of quantum state transfer from photons to atoms and back. This in turn can be used to improve the performance of quantum networks and repeaters, as […]
September 19, 2019