Quantum Simulations with Superconducting Circuits

Using a well-controlled quantum system to simulate complex quantum matter is an idea that has been put forward by Feynman around 30 years ago and seen some beautiful realisations with ultra-cold atoms in the last decade. Recently superconducting circuits featuring Josephson junctions have been discovered as an alternative technological platform with possibilities for quantum simulations that may complement the successes of ultra-cold atoms.  In these devices, oscillating currents of bound electron pairs, so called Cooper pairs, can maintain quantum coherence for a long time in circuits that are patterned on the surface of a microchip in an environment at milli-Kelvin temperatures. The considered quantum particles are thus microwave photons of the electromagnetic fields associated to the superconducting currents and their interactions are generated by Josephson junctions that are integrated in the circuit. Some background for this can be found in Houck et al., “On-chip quantum simulation with superconducting circuits”, Nature Physics 8, 292–299 (2012). In this project we want to explore the possibilities for simulating quantum magnetism in superconducting circuits. The task will thus be to design suitable circuits and show how their quantum dynamics can emulate a quantum magnet, i.e. a lattice of interacting spins.

This will be completed by assessing the robustness of a potential realisation with respect to noise sources that will inevitably be present in an experiment and by devising suitable ways for verifying the functionality of the quantum simulator via measurements.

Please send inquiry emails to Dr. Michael Hartmann at M.Hartmann@hw.ac.uk