Materials Research Laboratory
http://illinois.edu/calendar/list/79
Event calendar for the Frederick J. Seitz Materials Research Laboratory (an interdisciplinary research facility within the UIUC College of Engineering)Day After Thanksgiving - Designated Holiday
http://illinois.edu/calendar/detail/79/29077147
Special Eventhttp://illinois.edu/calendar/detail/79/29077147Fri, 27 Nov 2015 08:30:00 CSTInstruction resumes
http://illinois.edu/calendar/detail/79/32765007
Academichttp://illinois.edu/calendar/detail/79/32765007Mon, 30 Nov 2015 08:30:00 CSTICMT Seminar: "Half-filled Landau level and topological insulator surfaces"
http://illinois.edu/calendar/detail/79/32946197
ICMT Seminarhttp://illinois.edu/calendar/detail/79/32946197Mon, 30 Nov 2015 12:00:00 CST<p>I will describe recent developments relating the physics of the half-filled Landau level in two dimensions to correlated surface states of topological insulators in three dimensions (and to certain quantum spin liquid phases). The resulting insights provide an interesting answer to the old question of how particle-hole symmetry is realized in composite fermion liquids. Specifically the metallic state at filling $\nu = \frac{1}{2}$ - described originally in pioneering work by Halperin , Lee, and Read as a liquid of composite fermions - was proposed recently by Son to be described by a particle-hole symmetric effective field theory distinct from that in the prior literature. I will describe physical justifications of this proposal both through modification of older pictures of composite fermions, and through the connections to topological insulator surfaces. I revisit the phenomenology of composite fermi liquids (with or without particle-hole symmetry), and show that their heat/electrical transport dramatically violates the conventional Wiedemann-Franz law but satisfies a modified one. </p>Materials Science and Engineering Colloquium
http://illinois.edu/calendar/detail/79/33046709
seminarhttp://illinois.edu/calendar/detail/79/33046709Mon, 30 Nov 2015 16:00:00 CST<p>Ethics panel discussion</p>ICMT Special Seminar: "Fractionalization and broken symmetries in the underdoped cuprates"
http://illinois.edu/calendar/detail/79/33059129
ICMT Seminarhttp://illinois.edu/calendar/detail/79/33059129Tue, 01 Dec 2015 10:00:00 CST<p>A number of recent experiments in the underdoped regime of the hole-doped cuprates have found evidence for an incommensurate charge density wave order. I'll present an overview of how this new discovery, and a panoply of other measurements, affects our understanding of the mysterious pseudogap phase. In particular, I'll demonstrate that the observed charge density wave order may be interpreted as a low-temperature instability of a fractionalized Fermi-liquid, where the electronic excitations are coupled to a background quantum spin-liquid. The pseudogap regime can then likely be described by such an unconventional metal, at least over intermediate length and energy scales. I'll discuss various theoretical approaches towards describing such a fractionalized Fermi-liquid in models appropriate for the cuprates and provide an outlook for the open problems in the field</p>Physics Colloquium: "Resonant scattering studies of electronic orders in quantum materials"
http://illinois.edu/calendar/detail/79/32844377
Physics Colloquiumhttp://illinois.edu/calendar/detail/79/32844377Wed, 02 Dec 2015 16:00:00 CST<p>Quantum materials are forged by designing and engineering new phases of matter in materials, such as transition metal oxides, that are characterized by a strong interplay between the charge, orbital, spin, and lattice degrees of freedom. Broken symmetries and resulting order parameters are the hallmarks of new, emergent electronic phases, raising an important experimental challenge: how do we identify and study ordered states in correlated materials?</p>
<p>Resonant x-ray scattering (RXS) is an increasingly popular and powerful tool for the study of ordering phenomena in solids thanks to its ability to selectively capture the fingerprints of various types of electronic orders associated to specific degrees of freedom. After introducing the technique, I will show a few examples of our RXS studies of charge-density-waves, which occur when electrons self-organize into periodic, wave-like patterns in a solid. In particular, I will discuss our recent results in the cuprate superconductors – revealing the universality and resolving the microscopic structure and symmetry of charge-density-waves across the phase diagram – and in the iridium tellurides – shedding new light on the role of ligand orbitals in the stripe-ordered phase.</p>ICMT Special Seminar: "Dynamical Response of Many Body Localized Systems."
http://illinois.edu/calendar/detail/79/33059130
ICMT Seminarhttp://illinois.edu/calendar/detail/79/33059130Thu, 03 Dec 2015 10:00:00 CST<p>Many-body localization (MBL) is the long sought-after generalization of Anderson localization to interacting systems. Many-body localized systems fail to thermalize, and display a variety of novel properties and phases that have no equilibrium analog. In this talk, I will review our rapidly evolving understanding of the MBL phase before describing the eigenstate properties and dynamical response of these phases in some detail. In particular, I will show how a slow local perturbation surprisingly induces a highly non-local charge response despite the localized nature of the phase. This effect lies beyond linear response theory and has implications for numerous fields, including topological quantum computation in quantum Hall systems and quantum control in disordered environments. I will also discuss the low-frequency Kubo conductivity of MBL systems, and discuss the crossover from the linear to the non-linear response regime with an emphasis on the time-scales and amplitudes of the drive. </p>Mr. Xiao Rui Guo, UIUC, "Mechanics of the Cell Membrane: Understanding Lipid Flippases"
http://illinois.edu/calendar/detail/79/32929489
Seminarhttp://illinois.edu/calendar/detail/79/32929489Thu, 03 Dec 2015 12:00:00 CSTCHBE 565: an International Paper Company Lecture Series, Prof. Wonhwa Cho, "In situ Quantitative Imaging Reveals New Regulatory Roles of Lipids: A Cholesterol Story Never Told Before"
http://illinois.edu/calendar/detail/79/32973613
Lecturehttp://illinois.edu/calendar/detail/79/32973613Thu, 03 Dec 2015 14:00:00 CSTICMT Special Seminar: " Holographic Mapping of Many-Body Localized System by Spectrum Bifurcation Renormalization Group"
http://illinois.edu/calendar/detail/79/33059200
ICMT Seminarhttp://illinois.edu/calendar/detail/79/33059200Fri, 04 Dec 2015 10:00:00 CST<p>We introduce the spectrum bifurcation renormalization group (SBRG) as an improvement of the excited-state real space renormalization group (RSRG-X) for qubit models. Starting from a disordered many-body Hamiltonian in the full many-body localized (MBL) phase, the SBRG flows to the MBL fixed-point Hamiltonian, and generates the local integrals of motion and the matrix product state representations for all eigenstates. The method is applicable to both spin and fermion models with arbitrary interaction strength on any lattice in all dimensions, as long as the models are in the full MBL phase. As a Hilbert-space preserving RG, the SBRG also generates an entanglement holographic mapping, which duals the MBL state to a fragmented holographic space.</p>