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dc.contributor.advisorCohen, Adam Ezra
dc.contributor.authorYang, Nan
dc.date.accessioned2013-03-18T19:38:55Z
dash.embargo.terms2014-02-06en_US
dash.embargo.terms2014-02-06
dc.date.issued2013-03-18
dc.date.submitted2012
dc.identifier.citationYang, Nan. 2012. Molecules in Sculpted Fields: Magnetic Field Effects and Multipole Transitions. Doctoral dissertation, Harvard University.en_US
dc.identifier.otherhttp://dissertations.umi.com/gsas.harvard:10684en
dc.identifier.urihttp://nrs.harvard.edu/urn-3:HUL.InstRepos:10436344
dc.description.abstractThis thesis describes work related to the theme of sculpted electromagnetic fields - engineered fields with particular spatial patterns - and their interactions with molecules. We are motivated by the following questions: what are ways of detecting spatial patterns in electromagnetic fields? What are possible applications of spatially engineered fields? Are there molecular transitions that are dark to plane waves but that can be probed by sculpted fields? The first part of this thesis is in the area of magnetic field effects in chemistry. We focus on magnetic field modulated fluorescence, which provides a convenient method for imaging magnetic field strength. We proposed and demonstrated a fluorescence technique that allows imaging through strongly scattering media. We achieve this by exploiting the fact that most materials do not scatter magnetic field. This allows us to project a magnetic field pattern beyond the scattering surface. The magnetic field dependent fluorescence then allows us to map out the object of interest. We constructed a setup that demonstrates 2D imaging using this technique. We synthesized new molecular systems to enhance the sensitivity to magnetic field. We characterized and compared these molecules with steady state fluorescence spectroscopy, transient fluorescence and transient absorption measurements. The results reveal patterns that point to directions for engineering chemical systems to further enhance their magnetic field sensing properties. The second portion of this thesis is a theoretical study of the molecular multipole transitions and their couplings to local electromagnetic quantities. Using a semiclassical approach, we performed a multipole expansion of molecular transitions driven by monochromatic radiation. We derived the local electromagnetic quantities that couple to different multipole transitions and observables such as circular dichroism and magnetic circular dichroism. It was observed that certain transitions are dark to plane waves, but could be probed by simple spatial arrangements such as superpositions of plane waves. Experiments for their detection are also proposed.en_US
dc.description.sponsorshipEngineering and Applied Sciencesen_US
dc.language.isoen_USen_US
dash.licenseLAA
dc.subjectPhysical chemistryen_US
dc.subjectElectromagneticsen_US
dc.titleMolecules in Sculpted Fields: Magnetic Field Effects and Multipole Transitionsen_US
dc.typeThesis or Dissertationen_US
dc.date.available2014-02-06T08:30:30Z
thesis.degree.date2012en_US
thesis.degree.disciplineApplied Physicsen_US
thesis.degree.grantorHarvard Universityen_US
thesis.degree.leveldoctoralen_US
thesis.degree.namePh.D.en_US
dc.contributor.committeeMemberMahadevan, Lakshminarayananen_US
dc.contributor.committeeMemberWalsworth, Ronalden_US
dc.contributor.committeeMemberKhaneja, Navinen_US
dash.contributor.affiliatedYang, Nan


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