Alumni
Peiyuan Mao Meg Urry 
Quantitative Researcher Akuna Capital Blazar Demographics: Intrinsic Properties of JetDominated Active Galactic Nuclei Blazars with their Dopplerboosted relativistic jets are perfect laboratories to study jet physics and provide crucial insights into jet mechanism, black hole spin, and growth history of the host galaxy. However, the blazar samples we observe are highly biased subsets of the true population because of the complicated shape of their spectral energy distributions. Thus to infer the intrinsic properties of blazars we have to extrapolate from the biased samples — and there are two opposing... more 

Brendon O'Leary David DeMille 
In search of the electron's electric dipole moment in thorium monoxide: an improved upper limit, systematic error models, and apparatus upgrades Searches for violations of discrete symmetries can be sensitive probes of physics beyond the Standard Model. Many models, such as supersymmetric theories, introduce new particles at higher masses that include new CPviolating phases which are thought to be of order unity. Such phases could generate measurable permanant electric dipole moments (EDMs) of particles. The ACME collaboration has measured the electron’s EDM to be consistent with zero with an order of magnitude improvement in... more 

Saehanseul Oh John Harris 
Postdoctoral Associate Brookhaven National Lab Correlations in particle production in protonlead and leadlead collisions at the LHC In highenergy heavyion collisions at the Large Hadron Collider (LHC), a hot and dense state of matter called the QuarkGluon Plasma (QGP) is formed. The initial collision geometry and the subsequent expansion during the QGP stage result in the correlations of produced particles, through which the properties of the QGP can be investigated. Two analyses based on the geometrical correlations of produced particles, one in protonlead (p–Pb) collisions and the other in leadlead (Pb–Pb... more 

Andrei Petrenko Robert Schoelkopf 
Enhancing the Lifetime of Quantum Information with Cat States in Superconducting Cavities The field of quantum computation faces a central challenge that has thus far impeded the fullscale realization of quantum computing machines: decoherence. Remarkably, however, protocols in Quantum Error Correction (QEC) exist to correct qubit errors and thus extend the lifetime of quantum information. Reaching the "breakeven" point of QEC, at which a qubit's lifetime exceeds the lifetime of the system's constituents, has thus far remained an outstanding goal.... more 

Toshihiko Shimasaki David DeMille 
Continuous Production of 85Rb133Cs Molecules in the Rovibronic Ground State via ShortRange Photoassociation We present our results on continuous production of ultracold ^{85}Rb^{133}Cs molecules in the rovibronic ground state via shortrange photoassociation (PA). Starting with ultracold Rb and Cs atoms trapped in dualspecies darkSPOT MOT, we photoassociate a pair of Rb and Cs atoms into an excited molecular state, which decays into the electronic ground state by spontaneous emission. We apply depletion spectroscopy to the RbCs system and establish a rotationallyresolved, stateselective detection... more 

Jukka Vayrynen Leonid Glazman 
Electron transport along the edge of a topological insulator A twodimensional topological insulator has a gap for bulk excitations, but conducts on its boundaries via gapless edge modes. Timereversal symmetry prohibits elastic backscattering of electrons propagating within the edge, leading to quantized conductance at zero temperature. Inelastic backscattering, present at finite temperature, breaks the quantization and increases the edge resistance; the resistance of a long edge acquires a linear dependence on its length. A phenomenological... more 
Filip Kos David Poland 
Postdoc UC Berkeley Bootstrapping 3D CFTs We use the method of conformal bootstrap to systematically study the space of allowed conformal field theories (CFT) in three spacetime dimensions. We consider the crossing symmetry equations coming from the correlators of several lowest dimension operators in a given CFT and show how to setup the semidefinite program to explore the constraints implied by the equations. Constraints lead to general bounds on dimensions and 3point functions of the operators in CFT. Three classes of CFTs... more 

Tomomi Sunayama Nikhil Padamanabhan 
Postdoctoral Fellow Kavli Institute of Physics and Mathematics of the Universe Using galaxy surveys as a precision tool to measure dark energy Future surveys will provide a deeper understanding of dark energy, dark matter, and early universe physics through the measurements of large scale structure. In particular, the baryon acoustic oscillation (BAO) method and the redshiftspace distortion (RSD) method aim to achieve subpercent precision on cosmological parameters. Understanding and reducing the systematics caused by the nonlinear evolution of gravitational structures and galaxy formation and evolution is crucial for future galaxy... more 

Mitchell Underwood Jack Harris 
Cryogenic Optomechanics with a Silicon Nitride Membrane The field of optomechanics involves the study of the interaction between light and matter via the radiation pressure force. Though the radiation pressure force is quite weak compared with forces we normally experience in the macroscopic world, modern optical and microwave resonators are able to enhance the radiation pressure force so that it can be used to both measure and control the motion of macroscopic mechanical oscillators. Recently, optomechanical systems have reached a regime where the... more 
Rostislav Boltyanskiy Eric Dufresne 
Senior Scientist Spheryx Mechanical Response of Single Cells to Stretch A living cell is a complex soft matter system far from equilibrium. While it consists of components with definite mechanical properties such as stiffness, viscosity, and surface tension, the mechanics of a cell as a whole are more elusive. We explore cell mechanics by stretching single fibroblast cells and simultaneously measuring their traction stresses. Upon stretch there is a sudden, drastic increase in traction stresses, often followed by a relaxation over a time scale of ~1min. Upon... more 

Diego Caballero Orduna Corey O'Hern 
Financial Risk Expert European Central Bank Computational Studies of Protein Structure Despite the abundance of crystallographic and structural data and many recent advances in computational methods for protein design, we still lack a quantitative and predictive understanding of the driving forces that control protein folding and stability. For example, we do not know the relative magnitudes of the sidechain entropy, van der Waals contact interactions, and other enthalpic contributions to the free energy of folded proteins. The... more 

Jane Cummings Sarah Demers 
Tau Polarization at a Hadron Collider: W to tau,nu and Z to tau,tau decays at ATLAS In this thesis, the first measurement of tau polarization at a hadron collider, and the first measurement of tau polarization in W boson decays to a tau and neutrino altogether, is presented. The measurement of tau polarization is a test of the structure of the vector (V) and axial vector (A) couplings of the W boson to the third generation leptons. Such a test is not possible with first and second generation leptons for which the helicity state is not accessible in a collider... more 

Arvin Kakekhani Sohrab IsmailBeigi 
Postdoctoral Researcher University of Pennsylvania Website Ferroelectrics to Tackle Fundamental Challenges in Catalysis Surface catalysis based on transition metals and their alloys has been one of the most important research fields in theoretical and experimental catalysis and chemistry. Recently, the development of a microscopic theoretical framework combined with the computational capability and accuracy of first principles calculations has changed the nature of this field from a largely trial and error approach to a predictive and controlled design process. In addition to deepening our knowledge of catalysis... more 

Nicole Larsen Daniel McKinsey 
An Effective Field Theory Analysis of The First LUX Dark Matter Search A wealth of astrophysical research supports the existence of dark matter in the universe, yet the exact nature of this unknown particle remains elusive. The Large Underground Xenon (LUX) experiment is a 370kg dualphase xenonbased time projection chamber (TPC) that seeks to detect dark matter candidates such as Weakly Interacting Massive Particles (WIMPs) through the light and ionization signals generated by their collisions with xenon nuclei. The first part of this talk details the design of... more 

Manuel Mai Corey O'Hern 
Outcome Prediction and Reconstruction for Systems of Ordinary Differential Equations I will present two related analyses of systems of ordinary differential equations (ODEs). The first one investigates outcome prediction in several systems of ODEs for the immune response to infection. We show that patienttopatient variability sets a fundamental limit on the outcome prediction accuracy. However, accuracy can be increased at the expense of delayed prognosis. In the second study, I develop a method to build, general nonlinear ODE models from time series data using machine... more 