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dc.contributor.advisorSandhu, Arvinderen_US
dc.contributor.authorRoberts, Adamen_US
dc.creatorRoberts, Adamen_US
dc.date.accessioned2012-06-08T18:57:03Z
dc.date.available2012-06-08T18:57:03Z
dc.date.issued2012
dc.identifier.urihttp://hdl.handle.net/10150/228120
dc.description.abstractThis dissertation describes the response of graphene and graphene fragments to ultrafast optical pulses. I will first describe how we created few-cycle optical pulses for interacting with the graphene lattice. These pulses are created through filamentation based pulse compression. I studied how the filamentation process can be optimized through simple means to create the shortest possible pulse. I then examine the extent to which graphene can withstand irradiation from intense ultra-fast pulses. I examine both the high intensity regime at which a single laser pulse will ablate the graphene and a more moderate regime that slowly degrades the graphene from long term exposure to ultrafast pulses. The knowledge lets us both identify a safe working regime for driving the graphene lattice with optical fields as well as use ultrafast lasers to create graphene nano-fragments down to 2nm. Next, I explore the ultrafast dynamics of photo-excited graphene. Graphene undergoes electronic band renormalization after photo exciting carriers. By measuring a differential transmission spectrum, small changes to the band structure can be quantified. I will explain how screened exchange and electron phonon self energies provide corrections to the band structure for different times after carrier excitation. Lastly, I will describe measurements that determine the extent of electron-electron correlations in graphene fragments. By measuring the energy of the two photon state and comparing it the lowest energy one photon state in graphene fragments, we can determine the strength of the correlations in graphene systems.
dc.language.isoenen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.subjectOptical Sciencesen_US
dc.titleTime Domain Spectroscopy of Grapheneen_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.leveldoctoralen_US
dc.contributor.committeememberJones, Jasonen_US
dc.contributor.committeememberBinder, Rolfen_US
dc.contributor.committeememberSandhu, Arvinderen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineOptical Sciencesen_US
thesis.degree.namePh.D.en_US
refterms.dateFOA2018-08-26T16:44:52Z
html.description.abstractThis dissertation describes the response of graphene and graphene fragments to ultrafast optical pulses. I will first describe how we created few-cycle optical pulses for interacting with the graphene lattice. These pulses are created through filamentation based pulse compression. I studied how the filamentation process can be optimized through simple means to create the shortest possible pulse. I then examine the extent to which graphene can withstand irradiation from intense ultra-fast pulses. I examine both the high intensity regime at which a single laser pulse will ablate the graphene and a more moderate regime that slowly degrades the graphene from long term exposure to ultrafast pulses. The knowledge lets us both identify a safe working regime for driving the graphene lattice with optical fields as well as use ultrafast lasers to create graphene nano-fragments down to 2nm. Next, I explore the ultrafast dynamics of photo-excited graphene. Graphene undergoes electronic band renormalization after photo exciting carriers. By measuring a differential transmission spectrum, small changes to the band structure can be quantified. I will explain how screened exchange and electron phonon self energies provide corrections to the band structure for different times after carrier excitation. Lastly, I will describe measurements that determine the extent of electron-electron correlations in graphene fragments. By measuring the energy of the two photon state and comparing it the lowest energy one photon state in graphene fragments, we can determine the strength of the correlations in graphene systems.


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