REU projects 2014

Accelerator and Beam Physics

Faculty: James Rosenzweig

Project: Teravolt-per-meter Wakefields in Plasma Excited by Femtosecond Electron Beams.  Recent initiatives at UCLA concerning ultra-short, GeV electron beam generation have been aimed at achieving sub-fs pulses capable of driving X-ray free-electron lasers (FELs) in single-spike mode. This uses of very low charge beams, which may allow existing FEL injectors to produce few-100 attosecond pulses, with very high brightness. Towards this end, recent experiments at the Stanford X-ray FEL (LCLS, first of its kind, built with essential UCLA leadership) have produced ~2 fs, 20 pC electron pulses. We are now developing experiments which us such pulses to excite plasma wakefields exceeding 1 TV/m, permitting a table-top TeV accelerator for frontier high energy physics applications. Students participating this experiment will be working on an extreme-high field magnetic optics system to focusing the beam to very ~100 nm transverse dimensions, where the surface Coulomb fields are also at the TV/m level. These conditions access a new, novel regime for high field for atomic physics, allowing frontier atomic physics experiments, including sub-fs plasma formation via barrier suppression ionization (BSI) for subsequent wake excitation. The REU student will also aid in developing the gas-jet and advanced ionization diagnostics for this ultra-fast atomic physics/plasma physics scenario. 

Astronomy

Faculty: Andrea Ghez

Project: Black Hole and Its Environment at the Galactic Center: High resolution images of the center of our Galaxy with the world's largest telescopes are giving us an unprecedented view of a supermassive black hole and its environs. Through precision measurement of stellar orbits we aim to address many fundamental questions about the formation and evolution of black holes and galaxies. Possible summer projects include studies of (1) how the observed young stars arrived in this region in which no young stars were expected, (2) how this region was depleted of giants, which were predicted to exist in large numbers, (3) searches for micro-lensing events and (4) simulations of observations with future large ground-based telescopes.

Faculty: Jean Turner

We will be working with working with radio and infrared data to characterize star formation properties in nearby galaxies.

Faculty: Edward Wright

Project: Learn about physical models for the thermal emission from asteroids, and apply a thermophysical model to asteroids detected in two epochs by WISE. The student will extend the model to include horizontal conduction.  The student may also learn how to validate tracklets that will be coming in from the NEOWISE reactivation this summer, and help remove bad tracks from the new data going to the Minor Planet Center.

Faculty: Michael Jura

Project: Project: Exoplanet: We are using optical and ultraviolet spectra of white dwarf stars to measure the elemental composition of accreted planetesimals. These studies provide a uniquely powerful tool to study the formation and evolution of rocky extrasolar planets.

Atomic Physics

Faculty: Wesley Campbell

Project: Experimental atomic physics: Construction, demonstration, and characterization of an interferometric laser pulse analyzer.  Mode-locked lasers are capable of producing bursts of light that are far too brief to be measured directly with modern electronic equipment.  Instead, the pulses themselves can be split into two copies and the interference between these copies (along with nonlinear optics) can be used to determine the pulse duration, shape, spectral bandwidth, and chirp.  These properties are of great interest in our group as we try to engineer designer pulses to effect control the motion of ultracold ions, neutral atoms, and neutral molecules.

Faculty: Eric Hudson

Project: Multiplexed laser wavelength analysis for the production of ultracold atoms  Our group at UCLA is working to produce samples of ultracold molecular ions in their absolute ground quantum state. Such samples have wide ranging applications including quantum computation and information, as well as testing the fundamentals of physics. Our production method uses ultracold laser-cooled atoms in a magneto-optical trap to cool co-trapped molecular ions. An important diagnostic in this work is the ability to measure the wavelength of the lasers used to cool the atoms. The REU student will help develop a fiber optic multiplexer to allow us to extend our current measurement capabilities to include rapid measurement of the various lasers used in our experiment. The student will learn methods of data acquisition and analysis using LabVIEW as well as an understanding of Atomic, Molecular, and Optical physics techniques. 

Biophysics

Faculty: Katsushi Arisaka

Project: Neurophysics of C. elegans: We are interested in how the neural network of a small animal processes external stimulations simultaneously and make a prompt decision to navigate its environment for survival. For this purpose, we are developing an advanced optical microscope to observe the entire 302 neurons of freely behaving C. elegans.   The REU student will participate in designing, construction and operation of the microscope. 

Biophysics/Neurophysics

Faculty: Mayank Mehta

Theoretical project: Brain consists of billions of neurons, a large fraction of which are active at the same time and they influence each other. Further, neural activity also shows oscillatory dynamics which governs neural interactions.  Our laboratory has developed a technique to measure the activity many neurons simultaneously during natural behavior. The goal of this project is to decipher how neurons influence other neuron's activity and vice versa in a self consistent fashion and the role of neural oscillators in coordinating this. Interested students should have very good grasp on either Matlab or Python programming language.

Experimental project: Our brains effortlessly create perception of space and time, but the mechanisms by which this occurs have remained mysterious. Towards this end we have developed a virtual reality system that manipulates the perception of space and time. The goal of the project is to develop hardware and software to control the virtual world. Interested students should have a strong grasp of digital electronics including microcontrollers and programming them.

Condensed Matter

Faculty: Ni NI

Project: Our research focuses on the characterization of physical properties and structures of materials through thermodynamic, transport, X-ray and neutron measurements, with an emphasis on the design, synthesis and crystal growth of new materials. Our interests span a wide spectrum of materials, from intermetallics to oxides, especially superconductors and strongly correlated electron systems showing unusual electronic and magnetic ground states that can be perturbed by chemical doping, applied pressure or magnetic field. We aim at synthesizing new materials with nontrivial properties, characterizing quantum phases, and examining the different energy scales in solids. The interplay of magnetism, superconductivity and structure will be of particular interest. 

Nuclear Physics

Faculty: Prof. Huan Z. Huang

Project: Study of Heavy Quark Interaction with QCD Matter: QCD partonic matter at extremely high temperature and energy density has been created in Au+Au collisions at Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). We will study heavy quark (Charm and Bottom) interactions with the QCD matter in central Au+Au collisions. Heavy quarks are produced mostly through the gluon-gluon fusion process during the initial impact of the colliding nuclei. After the initial production heavy quarks may scatter off partons in the QCD matter and suffer energy losses while traversing the QCD matter via gluon radiation or elastic scattering. We will investigate experimentally signatures of these heavy quark interactions with the QCD matter.

Plasma Physics

Faculty: Christoph Niemann

Plasma Physics of Hypersonic Aircraft: Aircraft moving at supersonic velocity create a shock wave and well-known “sonic-boom”. At even higher speeds in excess of Mach-10, shock heating becomes strong enough to create a dense plasma sheath. Plasma instabilities in this ionized gas-layer can be detrimental to radio-communication. This effect is well known from the “blackout” that occurs during re-entry of spacecraft into Earth’s atmosphere. Understanding these plasma layers and associated instabilities is important as hypersonic aircraft are now being designed that could travel from Los Angeles to New York in a few minutes. A new laboratory plasma-wind tunnel experiment at UCLA produces a hypersonic plasma sheath with a high-power laser-produced plasma in a magnetic field. The experiment investigates the effect of plasma instabilities on the scattering and transmission of radio waves. Electric- and magnetic-field gradients are characterized with magnetic flux probes over large spatial and temporal scales, while the frequency spectrum of plasma pulsations is investigated with floating potential probes. The student will learn to design and perform high-power laser-plasma experiments, and to perform and analyze complex measurements on plasmas with motorized probes using labview.

Faculty: Troy Carter

Project: Studies of the linear and nonlinear properties of Alfven waves in a laboratory plasma. Alfvén waves are a fundamental wave mode that arises in a plasma with a magnetic field.  These waves play a key role in a variety of laboratory and space plasmas including the solar wind, solar corona, and magnetic fusion devices.  Therefore, a fundamental understanding of the physics of these waves is important for a range applications from fusion energy to protection of satellites from space weather.

On the Large Plasma Device (LAPD) at UCLA, the linear behavior of these waves has been extensively studied; the focus has now turned to non-linear phenomena that may play a key role in real plasmas.  For example, Alfvén wave interactions and instabilities may help explain the wave spectrum observed by satellites in the solar wind as well as the anonymously high temperature of the solar corona.

We have an opening for an undergraduate summer student to work on this project.  Possible topics include: experiments aimed at launching sound waves and studying the interaction with Alfvén waves, theoretical calculations of Alfvénic instabilities that may play a key role in space plasmas, and characterization of Alfvén waves in a high beta plasma [Beta, the ratio of the plasma pressure to the magnetic pressure, is ~1 in the near-Earth solar wind, but much smaller in previous LAPD experiments].  The experimental projects may include hands on work on plasma sources and diagnostic circuits, probe construction and calibration, and/or data acquisition and analysis using Labview, Matlab, or IDL.

Solid State Physics

Faculty: HongWen Jiang

Project: Manipulation of Individual Electron Spins in Silicon Base Qubits: It is becoming increasingly apparent that qubits based on individual electron spins in Si have considerable potential for scalable quantum information processing. One of the attractions of a spin in Si is its long decoherence time. The tunable spin-orbital coupling and the ability to control the electron wavefunctions allow gate operations on the spins. The extensive collection of Si chipmaking techniques, cumulated over decades, is expected to be invaluable for developing scalable qubits. The REU student will join the postdocs and graduate students in the group to fabricate and characterize a Si qubit that is based spin exchange interactions.