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Optomechanics group

Research topics

  • Multimode optomechanics
  • Hybrid optomechanics
  • Quantum optomechanics

Associate Professor Aurélien Dantan
(dantan@phys.au.dk, +4587155676, 1522-424)

New project: Integrated optical sensors with nanostructured trampolines (PhD position available!)

This project, funded by the Danish Council for Independent Research, aims at developing ultrashort optical resonators composed of ultrathin, nanostructured vibrating mirrors for various sensing applications. By patterning thin suspended silicon nitride films with a subwavelength structure (high contrast grating) and assembling them to form micron-long optical cavities, highly wavelength-selective optomechanical sensors operating in a new regime will be realized. The high spectral selectivity combined the small cavity modevolume and the outstanding mechanical quality of the vibrating mirrors will be exploited for various sensing applications and for fundamental investigations of optical forces at the nanoscale.

Phonon dynamics in optomechanical arrays

This Villum Fonden-funded project aims at investigating phonon dynamics in optomechanical arrays of nanomembranes. Tensioned membranes made of silicon nitride and only tens of nanometres thick represent excellent nanomechanical resonators for optomechanical investigations. Amongst their virtues are their low effective mass (nanograms) and thickness, their record mechanical quality factors of several millions, and their ultralow absorption, which facilitate their integration in high-finesse optical resonators. The radiation pressure forces exerted by optical fields on periodic arrays of such membranes allows for engineering long-range effective interactions between the vibrational modes of the individual membranes. Such interactions will be exploited to study collective optomechanical phenomena, such as synchronization, and non-equilibrium thermodynamics in few-element systems.

Quantum optomechanics of movable membranes in optical cavities

Project description

This project aims at engineering novel optomechanical systems composed of thin, movable membranes positioned in the field of an optical resonator and investigating the effects of the radiation pressure exerted by the cavity light on the motion of the membranes, as well as the back-action of their motion onto the light, at the quantum level. The excellent optomechanical properties of these nanomembranes should make it possible to explore new regimes of optomechanics in which effects due to the quantized nature of the motion and the light could be observed and exploited.

Ultimately, these membranes are to be integrated in a cavity ion-trap system, such as the ones developed in the Ion Trap Group in Aarhus (http://phys.au.dk/forskning/forskningsomraader/amo/the-ion-trap-group/), in order to perform hybrid optomechanics experiments in which a well-controlled atomic system, such as a cloud of trapped, laser-cooled ions, can be made to interact with macroscopic mechanical oscillators.

Such optomechanical interfaces, which potentially combine optical, mechanical and electrical activations of thin mechanical oscillators, would have applications in metrology, photonic and quantum information processing sciences, as well as surface and nano-sciences.

This project is funded by a Sapere Aude forskningsleder grant from the Danish Council for Independent Research.

Contact person: Aurélien Dantan (dantan@phys.au.dk, +4587155676, 1522-424)

Project start: Dec. 1st 2012