Exploring nonclassical states of center-of-mass mechanical motion with superconducting magneto- and levitomechanics

SuperMeQ addresses three basic science goals in quantum technologies, targeting to gain new insights into quantum control over the center-of-mass motion of mechanical resonators: (i) We will push to the limits of decoherence mechanisms of massive objects, (ii) we will maximize the vacuum coupling of the center-of-mass motion of a mechanical resonator to a quantum system, and (iii) we will generate useful nonclassical states such as squeezed states or states with a negative Wigner function, which have direct relevance for quantum-enhanced force and inertial sensing. Our project follows a unique approach by realizing two complementary experimental platforms that are tailored to our goals and that are mutually beneficial through parallel development: (a) magnetically levitated superconducting microparticles that access a mass regime spanning more than seven orders of magnitude between picogram and sub-milligram masses, and that are expected to exhibit ultra-low mechanical decoherence, and (b) integrated clamped magnetic or superconducting mechanical resonators that are expected to reach strong vacuum coupling rates, two orders of magnitude larger than the state-of-the-art. Key in each of these approaches is that we will couple both types of mechanical resonator inductively to superconducting quantum circuits, which allow for full quantum control over the center-of-mass degree of freedom of the mechanical resonators. Our project results will lead to a breakthrough in the development and growth of novel quantum sensing technologies and give new insights into foundational aspects of quantum physics.