Alemán, BenjamínMiller, David2020-09-242020-09-242020-09-24https://hdl.handle.net/1794/25629Nanomechanical systems (NEMS) are some of humankinds most exquisite sensors of mass and force and have enabled the transduction of physical phenomena down to the single-phonon level. Despite incredible progress on the overall properties of mechanical resonators, development of large-scale arrays is only now beginning to be explored. Such arrays could be transformative in basic science, allowing for realization of topological metamaterials and studies of networks, and for applied devices, such as next-generation mass spectrometers and thermal imaging cameras. To make a NEMS array viable for these applications however, each NEMS device must have several desirable properties. First, all devices must have high mechanical quality factors (Q) combined with low mass, for high sensitivity. This requires both a fundamental knowledge of the origin of mechanical dissipation and viable engineering methods to maximize the Q for a given mass. Second, devices must have scalable control methods for tuning the frequency and exciting motion. No such devices that meet these requirements exist today and applications for NEMS arrays remain limited. Graphene NEMS have the potential to meet these needs, if some fundamental challenges can be addressed. Although graphene NEMS have low mass, they also have a relatively low Q. Furthermore, engineering methods to modify the shape of graphene NEMS are limited, making it difficult to tune and enhance their properties. Finally, like all other NEMS, tuning and control methods that scale to large arrays are sorely lacking. In this work, we will begin to address these needs in graphene NEMS through a compendium of studies. We will first use shape engineering to enhance the properties of graphene NEMS. Then, we will present a detailed study of the Q and demonstrate methods to enhance it. Finally, we will study actuation and control methods for graphene NEMS, including demonstration of an electo-optic method that is truly scalable. Together, these studies pave the way for future work on large-scale arrays of NEMS. This dissertation includes previously published and unpublished co-authored material.en-USAll Rights Reserved.FIBGrapheneNanotechnologyNEMSElectronic Thesis or Dissertation