The ability to control mechanical motion with optical forces has made it possible to cool mechanical resonators to their quantum ground states. The same techniques can also be used to amplify rather than reduce the mechanical motion of such systems. Here, we study nanomechanical resonators that are slightly buckled and therefore have two stable configurations, denoted 'buckled up' and 'buckled down', when they are at rest. The motion of these resonators can be described by a double-well potential with a large central energy barrier between the two stable configurations. We demonstrate the high-amplitude operation of a buckled resonator coupled to an optical cavity by using a highly efficient process to generate enough phonons in the resonator to overcome the energy barrier in the double-well potential. This allows us to observe the first evidence for nanomechanical slow-down and a zero-frequency singularity predicted by theorists. We also demonstrate a non-volatile mechanical memory element in which bits are written and reset by using optomechanical backaction to direct the relaxation of a resonator in the high-amplitude regime to a specific stable configuration.
Bibliographical noteFunding Information:
The authors thank M. Rooks (Yale Institute for Nanoscience and Quantum Engineering) for help with electron-beam lithography, and M. Power for help with device fabrication. The authors also acknowledge funding support from the DARPA/MTO ORCHID programme through a grant from the Air Force Office of Scientific Research (AFOSR). H.X.T. acknowledges support from a Packard Fellowship in Science and Engineering and a career award from the National Science Foundation. M.P. acknowledges a Rubicon fellowship from the Netherlands Organization for Scientific Research (NWO)/Marie Curie Cofund Action.