IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Microelectromechanical Systems (MEMS) Friday Sessions
       Session MM+BI+NS+EL+SS-FrM

Paper MM+BI+NS+EL+SS-FrM1
Optomechanical Effects in and Properties of Nanomechanical Resonant Structures

Friday, November 2, 2001, 8:20 am, Room 130

Session: New Frontiers in MEMS: NEMS and BioMEMS
Presenter: L. Sekaric, Cornell University
Authors: L. Sekaric, Cornell University
M. Zalalutdinov, Cornell University
S.W.P. Turner, Cornell University
A.T. Zehnder, Cornell University
J.M. Parpia, Cornell University
H.G. Craighead, Cornell University
Correspondent: Click to Email
Recently we reported optical excitation and parametric amplification@footnote 1@ of single-crystal silicon MEMS oscillators with resonant frequencies up to 1MHz. Utilizing the interferometric pattern of a laser beam in a Fabry-Pérot cavity formed by the oscillator, we demonstrated a mechanism which can be used both as a driving/amplification scheme and a detection scheme. Here we report observation of this phenomena in single-crystal silicon nanomechanical oscillators with frequencies up to 25MHz and with dimensions up to 2um. High mechanical quality factors (Qs) of these structures were instrumental in enabling us to observe these phenomena. Qs of micron-scale and sub micron structures have been observed to have been relatively low (~ 10@super 3@) as measured in vacuum and at room temperature. We succeeded in improving the Qs of these devices (~ 10@super 4@) at room temperature and high vacuum. We will describe the bulk and surface treatments used to achieve high Q. In addition, these structures act as passive modulators of the laser light at their resonant frequencies. The sensitivity of the measurement technique and the inherent amplification of the motion via the optical drive presents us with a very efficient interferometer/modulator easily integrable on chip. Our initial modeling shows that the laser power needed to set these devices into oscillation is only up to few tens of microwatts. Our long-standing interest in nanomechanical structures fabricated in different materials, presents us with a natural extension for our current and future work - clearly being at an advantage of using this driving scheme even with electrically insulating device layers and with no theoretical frequency limit. @FootnoteText@ @footnote 1@ M. Zalalutdinov, A. Olkhovets, A. Zehnder, B. Ilic, D. Czaplewski, H. G. Craighead, and J. M. Parpia, "Optically pumped paramagnetic amplification for micromechanical oscillators" , Appl. Phys. Lett., Vol. 17 (16) 181 (2001)).