# Alumni

 Supraja BalasubramanianBonnie Fleming Postdoctoral AssociateFermi National laboratoryA Diﬀerential Cross-Section Measurement of Muon Neutrino-Induced Charged Current Neutral Pion Production in MicroBooNEMicroBooNE is a liquid argon time projection chamber (LArTPC) on the Booster Neutrino Beam at Fermi National Laboratory. Its primary goals are to conduct a νe appearance search to investigate the nature of the anomalous low-energy excess of electromagnetic events observed by MiniBooNE, study neutrino-argon interactions, and conduct research and development for future large-scale argon based detectors such as DUNE. A signiﬁcant background for MicroBooNE’s νe appearance measurement... more Estella Barbosa de SouzaReina Maruyama ConsultantBoston Consulting GroupA Model-Independent Search for Dark Matter-Induced Annual Modulation Signal with the COSINE-100 Experiment Joshua BurtJohn Murray Large-Scale Organization of Microcircuit Specialization in Human CortexNeural circuit dynamics across a range of spatiotemporal scales endow the brain with specialized computational capabilities that subserve human cognition and behavior. Technological advances and big data initiatives in recent years have revolutionized our understanding of the brain’s multi-scale architecture. Yet there remains a major disconnect in linking large-scale dynamics of networked neural systems to their underlying circuit mechanisms. Biophysically-based computational modeling of... more Shany DanieliPieter van Dokkum NASA Hubble and Carnegie-Princeton Postdoctoral Fellow Institute for Advanced StudyWebsiteClues to the Nature of Dark Matter from Low-Mass Galaxies Outside the Local GroupThe primary motive for this thesis is the highly uncertain nature of dark matter, presumably the dominant substance in our universe. From an astronomical perspective, perhaps the perfect laboratories for investigating the nature of dark matter on small scales are low surface brightness, low mass galaxies. They are the most abundant type of galaxy in the universe. In the Local Group, they are found to be dark matter dominated and thus have larger portions of dark matter for their total mass. And... more Scott JensenYoram Alhassid Postdoctoral AssociateUniversity of Illinois, Urbana-ChampaignLattice Auxiliary-Field Quantum Monte Carlo Studies of the Unitary Fermi GasThe Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensate (BEC) crossover has been experimentally realized using Feshbach resonance techniques with ultracold atomic Fermi gases of 6Li and 40K. In the middle of this crossover is the unitary Fermi gas (UFG), in which the s-wave scattering length diverges and interactions are strongest. The UFG has many interesting properties including a particularly high critical temperature for superfluidity Tc ~ 0.15 TF (in units of the Fermi temperature... more William SweeneyA. Douglas Stone Data ScientistVideaHealthElectromagnetic Eigenvalue Problems and Nonhermitian Effects in Linear and Saturable ScatteringIn this thesis we address a series of new problems in non-hermitian optical scattering – linear and nonlinear – with increasing degrees of complexity. We develop the theory of reflectionless scattering modes (RSMs), introducing a novel and broad class of impedance-matched eigenproblems: for a given structure, find the incident wavefronts and frequencies which are not partially reflected at all, but are instead transmitted through the scatterer, or dissipated within it. The RSM... more Kyle VanderWerfCorey O'Hern Geometry and Contact Mechanics of Athermal Jammed Packings of Frictionless Spherical and Nonspherical ParticlesI perform computational studies of quasistatically jammed packings of frictionless particles of a variety of shapes. Each of the four studies presented in this dissertation focuses primarily on the connection between the mechanical and geometric properties of these packings – specifically, how physical aspects such as force and torque balance, pressure, and shear and bulk moduli correlate with (a) constituent particle shape, (b) the degree of particle ordering in packings, and (c) the... more Christian WeberKeith Baker Research Associate PhysicsBrookhaven National LabNew Search for H→ZZ_d→4l using pp collision data at √s=13 TeV with the ATLAS detectorIn 2012 the ATLAS and CMS experiments both reported the discovery of a new particle in the remnants of high-energy proton-proton collisions. The particles properties were consistent with the ones of the Standard Model Higgs boson. Its discovery, 58 years after its postulation, marked the completion of the Standard Model of Particle Physics.   Subsequent data taking at both experiments continued to record Higgs boson decays. With this increased dataset, we are now... more Hao YanSimon Mochrie Positional Fluctuations in Synthetic and Living Polymer SystemsChromatin organization is inextricably linked to its dynamics. The loop extrusion factor (LEF) model provides a framework for how topologically associating domains (TADs) arise: cohesin or condensin extrude DNA loops, until they encounter boundary elements, namely CTCF. However, a characteristic subdiffusive behavior of MSD is observed in fission yeast on the seconds timescale and experiments show that cohesin or condensin largely constrains chromatin mobility. Such finding is inconsistent with... more Mengzhen ZhangA. Douglas Stone Postdoctoral AssociateUniversity of ChicagoProperties and Applications of Gaussian ProcessesGaussian states, operations, and measurements are central building blocks for continuous-variable quantum information processing which paves the way for abundant applications, especially including network-based quantum computation and communication. To make the most use of the Gaussian processes, it is required to understand and utilize suitable mathematical tools such as the symplectic space, symplectic algebra, and Wigner representation. Applying these mathematical tools to practical quantum... more
 Robert BlumSean Barrett Postdoctoral Associate (Barrett)Yale UniversityApplying novel NMR techniques to many-body spin systems, and novel reconstruction techniques to NMR dataThis experimental thesis focuses on two distinct themes: developing NMR techniques to probe many-body spin systems, and extracting the maximum amount of information from the minimum amount of data. For the first theme, I describe the first NMR observations of discrete time crystal signatures. A discrete time crystal (DTC) is a many-body quantum state where a driven system exhibits discrete time translational symmetry breaking. A surprising aspect of our DTC signatures is that they were detected... more Luke BurkhartRob Schoelkopf Postgraduate AssociateYale University, Applied PhysicsError-Detected Networking for 3D Circuit Quantum ElectrodynamicsQuantum machines have the potential to serve as groundbreaking tools for scientific discovery in the coming decades. As the complexity of these devices increases, it may be necessary to borrow ideas from complex classical systems, and build them in a modular fashion, with independently designed, optimized, and tested components, networked together into a functioning whole. To build a modular machine from superconducting circuits requires the ability to perform operations between quantum bits... more Arpit DuaMeng Cheng & Liang Jiang UQM-IQIM Postdoctoral scholarCaltechStructure of fracton stabilizer models In recent years the study of topological phases of matter has moved to the forefront of theoretical condensed matter physics. This has been fueled in part by the theorized existence of exotic phases of matter that can serve as topological quantum memories and computers. The classification of topological phases of matter in two spatial dimensions in terms of anyon theories, or modular tensor categories, and chiral central charges forms the cornerstone of the subject. For the special case of 2D... more Raymond EhlersHelen Caines Postdoctoral AssociateOak Ridge National Lab Jet-Hadron Correlations Measured in Pb--Pb Collisions at $\sqrt{s_{\text{NN}}} = 5.02$ TeV with ALICEQuantum Chromodrynamics (QCD) describes the interactions of quarks and gluons. Due to asymptotic freedom, sufficiently high energy density can cause matter to transition to a deconfined state of matter known as the Quark-Gluon Plasma. As partons propagate through this QCD medium, which can be formed in ultra-relativistic heavy-ion collisions, they lose energy and the resulting jets are known to be modified in a phenomena known as jet quenching. This thesis investigates potential path length... more Judith HoellerNicholas Read Postdoctoral AssociateTBDTopological quantization of Berry phases in quantum and classical systemsBerry phases are known to occur for a spin 1/2 in a slowly varying magnetic field in quantum mechanics, and for the polarization of light in a gently twisted optical fiber in classical optics. Such Berry phases take on continuous values. I describe two systems in which Berry phases are topologically quantized to discrete values: (1) cold atoms in accelerated optical lattices, and (2) dissipative two level systems coupled to radiation with a slowly varying phase offset. (1) Cold atoms in... more