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A NEW FOUNDATION OF MUSIC: SAMPLING AND ITS IMPACT ON THE CREATIVE PROCESS
The term “sampling”, when talking about music, has taken on a number of differentmeanings to reflect its many usages in recorded and electronic music. These meanings and
definitions are as varied as the individual sampling practices, but all of them are born of the
capabilities, limitations and product design of specific pieces of hardware. Drum machines and
samplers have become so ubiquitous across all genres of music that we often take for granted the
seismic shifts in the conceptualization of primary musical materials that are a result of these
developments in music technology. These shifts don’t only manifest in recorded music or live
electronics music, they are also plainly evident in notated concert music.
While the rise of the microchip and the resulting technology of the 1980s made electronicmusic more accessible to musicians outside of academia and high-end recording studios, the
groundwork for the musical developments of that era was laid over the course of almost forty
years, from musique concrète all the way through DIY DJ-ing. This dissertation isn’t a historical
recounting of these developments, but instead analyzes the manner in which specific design
choices encouraged musicians of all backgrounds to think outside the electronic box
TOPOLOGICAL PHASES OF MATTER IN CRYSTALS AND SUPERCONDUCTING QUANTUM CIRCUITS
Topological states and topologically ordered phases are a cornerstone of physics, with applications ranging from quantum materials to quantum error correction. The robust quantum properties of topological materials may be harnessed for technology. On the other hand, topological order is a powerful tool for the storage and manipulation of quantum information with high fidelity. In this dissertation, I describe the experimental observation of many topological phases of matter using photoemission spectroscopy and quantum simulation. To start, I focus on magnets with a kagome crystal structure, where quantum interference generically leads to Dirac crossings and flat bands. In quasi-two dimensional TbMnSn, a Chern gapped state is evidenced by photoemission band structure maps, a Landau fan in tunneling spectroscopy data, and in-gap edge states. Then in the three-dimensional kagome ferromagnet CoSnS, the annihilation of Weyl points is demonstrated through careful photoemission measurements with varying temperature.
Next, I explore an extension of Weyl semimetals: higher-fold chiral semimetals. These materials host fermionic excitations that cannot be described by the standard model, where bands with large Chern number give rise to long helicoid Fermi arcs. In the topological chiral crystal NiRhSi, I fully characterize a higher-fold fermion by imaging all relevant bulk bands and extracting the Chern number of each band gap through the bulk-boundary correspondence. Then in stoichiometric RhSi and CoSi, I demonstrate a generic behavior of Fermi arcs to generate van Hove singularities. These van Hove points may be important for generating correlated states, such as the charge order recently observed in CoSi. The large topological nontrivial energy window in these compounds is also advantageous to search for quantized optical response.
Finally, I present results from a Google superconducting quantum processor demonstrating the quantum simulation of lattice gauge theory, which is equivalent to the toric code in the zero-field limit. The quantum dynamics in topological and trivial phases show deconfined and confined behavior, respectively. In addition, because the simulation is in two bona fide spatial dimensions, our protocol can be leveraged to visualized the dynamics of a Wegner-Wilson string. String breaking is also observed.
With the field of topological quantum materials headed toward ever more correlated platforms, the need for precise many-body quantum simulation techniques is paramount. At the same time, breakthroughs in quantum materials may put forward superior platforms for quantum computing. This dissertation promotes the budding synergetic relationship between quantum matter and quantum computers