Periodic Reporting for period 1 - ELOTEQ (Interfacing Levitated Optomechanics with Superconducting Qubits)
Reporting period: 2019-05-01 to 2020-04-30
(1) ELOTEQ showed how highly charged dielectric nanoparticles can be coherently interfaced with superconducting circuitry. I demonstrated that the rotational and translational motion of charged nanorotors suspended in a Paul trap induces a current in the endcap electrodes, which couples to the quantum state of an attached superconducting Cooper pair box. An ultra-fast protocol of qubit rotations and measurements enables the preparation and read-out of nanoparticle quantum superposition states on nanosecond timescales and in the presence of ambient decoherence channels.
ELOTEQ also developed the theory of how arbitrarily charged nanoparticles in a Paul trap interact with homogeneous magnetic fields. The rotational motion of a charged particle induces a magnetic dipole moment, which tends to align the particle rotation axis with the external field. We showed that time-dependent magnetic fields can induce mechanical rotation and we currently work on proposing an experiment to observe and exploit this effect. Moreover, we proposed and analysed an experiment carried out in the group of James Millen (King’s College London), which tests non-equilibrium thermodynamics with charged particles.
(2) In addition, ELOTEQ developed schemes to perform orbital angular momentum interference with Bose-Einstein condensates in torus traps, a protocol to entangle two tweezer-levitated nanoparticles via coherent scattering, and the theoretical framework to observe and exploit quantum persistent tennis-racket oscillations. We also demonstrated how elliptic coherent scattering enables simultaneous rotational and translational groundstate cooling of aspherical nanoparticles, and, I provided theory support for the first experimental observation of Bragg diffraction of molecules.
The work of ELOTEQ has been disseminated in 13 talks at scientific conferences and invited seminars, two public outreach talks, and two public science events at Imperial College London. Two manuscripts have been published recently in peer-reviewed journals, one manuscript has been accepted in Physical Review Letters and selected as Editor’s Suggestion, further three works are currently under review, and several are in preparation.