QFS 2016 Book of Abstracts

Abstracts

P1.8 Universal non-linear I-V at an impurity quantum critical point Chung Chung-Hou(1), Baranger Harold(2), Lin Chao-Yun(1), Zhang Gu(2), Ke Chung-Ting(2), and Finkelstein Gleb(2) 1) National Chiao-Tung University, Department of Electrophysics, 1001 University Rd., HsinChu, Taiwan, R.O.C. 300 2)Duke University, Department of Physics, Physics Bldg., Science Dr. Box 90305 Durham, NC 27708 USA Universal non-linear I-V at an interacting quantum critical point (QCP) is often out of reach theoretically. Here, however, we provide a striking example of analytically accessible QCP in a spinless quantum dot coupled to Ohmic resistive leads through a symmetrical double-barrier, realized in recent experiments. The transmission approaches unity (on resonance) with a weak backscattering at low temperature and applied bias when tuned exactly to the QCP. Drawing on the dynamical Coulomb blockade theory via bosonization and re-fermionization, we obtain analytically the full I-V curve, in excellent agreement with experiments. P1.9 Optimized Jastrow correlations for a one dimensional periodic system Panholzer Martin Johannes Kepler University, Institute for Theoretical Physics, 4040 Linz Jastrow correlations are a powerful tool to describe properties of strongly correlated systems. Mostly these correlations are optimized within variational Monte Carlo (VMC) calculations, especially for electronic systems. On the other hand there are diagrammatic methods like Hyper Netted Chain (HNC) summations, which are very successfully in describing Helium fluids. A drawback, compared to VMC is the necessary approximation of elementary diagrams. This is compensated by the lower numerical demand, the parameter free optimization and the possibility to deal with excited states. The extension of the HNC-method (and also the Fermion version FHNC) to periodic systems, i.e. a inhomogeneous density with a certain period, is presented. Special emphasis is given to the numerical feasibility of the approach. It is shown that by exploiting the symmetry even realistic three dimensional problems can be treated. The result for a inhomogeneous but periodic one dimensional electron gas is presented. As starting point we use a sinusoidal density. With this approach we describe the transition from a regime where the local density approximation (LDA) is a good approximation to a regime where it fails. Finally an outlook is given to possible applications e.g. electrons in solids, Helium adsorbed on surfaces and metal-Mott insulator transition.

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