title: Observation of optomechanical buckling transitions.
abstract: Correlated phases of matter provide long-term stability for systems as diverse as solids, magnets and potential exotic quantum materials. Mechanical systems, such as buckling transition spring switches, can have engineered, stable configurations whose dependence on a control variable is reminiscent of non-equilibrium phase transitions. In hybrid optomechanical systems, light and matter are strongly coupled, allowing engineering of rapid changes in the force landscape, storing and processing information, and ultimately probing and controlling behaviour at the quantum level. Here we report the observation of first- and second-order buckling transitions between stable mechanical states in an optomechanical system, in which full control of the nature of the transition is obtained by means of the laser power and detuning. The underlying multiwell confining potential we create is highly tunable, with a sub-nanometre distance between potential wells. Our results enable new applications in photonics and information technology, and may enable explorations of quantum phase transitions and macroscopic quantum tunnelling in mechanical systems.
authors.affiliation: Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: H
authors.initials: H
authors.lastname: Xu
authors.affiliation: Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA.|National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: U
authors.initials: U
authors.lastname: Kemiktarak
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: J
authors.initials: J
authors.lastname: Fan
authors.affiliation: Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA.|Joint Center for Quantum Information and Computer Science, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: S
authors.initials: S
authors.lastname: Ragole
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: J
authors.initials: J
authors.lastname: Lawall
authors.affiliation: Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA.|National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.|Joint Center for Quantum Information and Computer Science, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Taylor