In fluids, micro and nanomechanical devices can detect small forces for biomedical, biological and chemical applications. Recently, hybrid systems combining mechanical and optical devices have been explored [1], enabling the measurement of mechanical signals with unprecedented sensitivity and speed. Our team has for example demonstrated nanomechanical motion detection at gigahertz frequency with a sensitivity of 10(-17) m/√(Hz) [2,3], several orders of magnitude beyond conventional techniques at use for nanomechanical devices.
In liquids, the implications of this breakthrough are manifold [3] : the control of mechanical forces in a fluidic environment becomes accessible at ultra-high frequency, at a very local spatial scale (micro-nano) and with an unequalled level of precision [4]. Not only will chemical and biological sensors directly benefit from these developments, but new fundamental physics as well.
A first aim of this PhD project is to develop a nano-optomechanical (NOM) fluidic sensor integrated on a semiconductor chip (see illustration of a NOM resonator interacting with a liquid). A second aim is to investigate ultra-high frequency fluidic behaviors, in unconventional regimes that were inaccessible until now. These interdisciplinary researches will combine optics, nanomechanics, fluidics, clean–room techniques, modeling and theoretical aspects. They will take place within a multi-partner European project starting 2017, in tight collaboration with several groups abroad.
[1] I. Favero, and K. Karrai. Nature Photonics 3, 201 (2009)
[2] L. Ding, C. Baker, P. S., A. L, S. Ducci, G. Leo and I. Favero. Phys. Rev. Lett. 105, 263903 (2010).
[3] E. Gil-Santos, C. B, D. T. N, W. H, C. G, A. L, S. D, G. L and I. Favero. Nature Nano 10, 810 (2015).
[4] J. Tamayo. Mass sensing : optomechanics to the rescue. Nature Nano. 10, 738 (2015).