Mesoscopic quantum science and metrology with levitated mechanical systems

The first major effort will be to controllably synthesize (Pauzauskie) non-spherical (rod- and disc-shaped) particles with well-defined crystallographic phases for controlling and cooling torsional and rotational motion in optical traps (Geraci,Kane, Vamivakas). New possibilities opened up by the mechanical oscillator’s in situ tunability and the coupling among the translational, torsional, and rotational motion will be developed (Bhattacharya). In parallel, investigation of flexural modes of levitated membranes is especially interesting for studies of mechanical systems in the quantum regime, since the frequencies of micron-scale particles can be of order 100 MHz or greater, and can be adjusted by rotation-induced tension. Understanding the loss mechanisms of these modes and how they relate to the material properties of the levitated membrane will be a major goal of initial research. Finally, we will explore the magnetic levitation of LHe drops and the coupling between their Hz-scale rotations, kHz-scale surface waves, and MHz-scale acoustic waves. All of these modes can be optically controlled due to LHe’s extreme mechanical compliance and the drop's ability to store large photon numbers within its optical whispering gallery modes. This should be an ideal system in which to use "optical dilution" to reach the ground state (Harris, Bhattacharya). The goal of these efforts will be to implement protocols for active and passive cooling that utilize the individual and the coupled DOFs. An exciting path to emerge will be the first experimental investigations into rotational mechanics and the quantum physics of levitated harmonic oscillators and rigid rotors