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dc.contributor.advisorLoncar, Marko
dc.contributor.authorHui, Pui Chuen
dc.date.accessioned2014-10-21T18:51:40Z
dash.embargo.terms2015-01-01en_US
dash.embargo.terms2015-01-01
dc.date.issued2014-10-21
dc.date.submitted2014
dc.identifier.citationHui, Pui Chuen. 2014. Optomechanics and nonlinear mechanics of suspended photonic crystal membranes. Doctoral dissertation, Harvard University.en_US
dc.identifier.otherhttp://dissertations.umi.com/gsas.harvard.inactive:11841en
dc.identifier.urihttp://nrs.harvard.edu/urn-3:HUL.InstRepos:13068536
dc.description.abstractThe recent demonstration of strong interactions between optical force and mechanical motion of an optomechanical structure has led to the triumphant result of mechanical ground-state cooling, where the quantum nature of a macroscopic object is revealed. Another intriguing demonstration of quantum physics on a macroscopic level is the measurement of the Casimir force which is a manifestation of the zero- point energy. An interesting aspect of the Casimir effect is that the anharmonicity of the Casimir potential becomes significant when the separation of microscale objects is in the sub-100nm regime. This regime is readily accessible by many of the realized gradient-force-based optomechanical structures. Hence, a new avenue of probing the Casimir effect on-chip all-optically has become available. We propose an integrated optomechanical platform, consisting of a suspended photonic crystal membrane evanescently coupled with a silicon-on-insulator substrate, for (i) measuring the Casimir force gradient and (ii) counteracting the attractive force by exerting a resonantly enhanced repulsive optical gradient force. This thesis first presents the full characterization of the optomechanical properties of the system in vacuo. The interplay of the optical gradient force (optomechanical coupling strength \(g_{om}/2\pi=- 66GHz/nm\)) and the photothermal force manifested in the optical spring effect and dynamic backaction is elucidated. Static displacement by the repulsive force of 1nm/mW is also demonstrated. In the second part of the thesis, the nonlinear mechanical signatures upon a strong coherent drive are reported. By resonantly driving the photonic crystal membrane with a piezo-actuator and an optical gradient force, we observed mechanical frequency mixing, mechanical bistability and non-trivial interactions of the Brownian peak with the driving signal. Finally we present our recent progress in establishing electro- static control of individual photonic crystal membranes to reduce and calibrate the electrostatic artifact which plagues Casimir measurements. The results discussed in this thesis point towards an auspicious future of a complete realization of a Casimir optomechanical structure and novel applications with nonlinearity afforded by the Casimir force and the optical gradient force.en_US
dc.description.sponsorshipEngineering and Applied Sciencesen_US
dc.language.isoen_USen_US
dash.licenseLAA
dc.subjectOpticsen_US
dc.subjectPhysicsen_US
dc.subjectNano-mechanicsen_US
dc.subjectNonlinear mechanicsen_US
dc.subjectOptical forceen_US
dc.subjectOptomechanicsen_US
dc.subjectPhotonic crystal membraneen_US
dc.titleOptomechanics and nonlinear mechanics of suspended photonic crystal membranesen_US
dc.typeThesis or Dissertationen_US
dash.depositing.authorHui, Pui Chuen
dc.date.available2015-01-01T08:31:06Z
thesis.degree.date2014en_US
thesis.degree.disciplineEngineering and Applied Sciencesen_US
thesis.degree.grantorHarvard Universityen_US
thesis.degree.leveldoctoralen_US
thesis.degree.namePh.D.en_US
dc.contributor.committeeMemberLoncar, Markoen_US
dc.contributor.committeeMemberCapasso, Federicoen_US
dc.contributor.committeeMemberHu, Evelynen_US
dash.contributor.affiliatedHui, Pui Chuen


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