The Effect of Interaction on Shot Noise in The Quantum Limit

We employ a non-linear sigma model defined on a Keldysh contour to study the current and the current noise in a diffusive micro-bridge in the presence of electron-electron interactions. Out of equilibrium the fluctuation-dissipation theorem (FDT) does not apply, hence these two quantities are not simply interrelated. For a two-dimensional electron gas (2DEG) we obtain logarithmic singularities in the low frequency limit. PACS Nos. 71.10.Ay, 71.23.An, 73.50.TdComment: Submitted to the proceedings of 36 Renconters de Moriond "Electronic correlations: from meso- to nano-physics". One figure adde

Electronic Mach-Zehnder interferometer as a tool to probe fractional statistics

We study transport through an electronic Mach-Zehnder interferometer recently devised at the Weizmann Institute. We show that this device can be used to probe statistics of quasiparticles in the fractional quantum Hall regime. We calculate the tunneling current through the interferometer as the function of the Aharonov-Bohm flux, temperature and voltage bias, and demonstrate that its flux-dependent component is strongly sensitive to the statistics of tunneling quasiparticles. More specifically, the flux-dependent and flux-independent contributions to the current are related by a power law, the exponent being a function of the quasiparticle statistics.Comment: 22 pages; 8 figure

Controlling for Lexical Closeness in Survey Research: A Demonstration on the Technology Acceptance Model

Word co-occurrences in text carry lexical information that can be harvested by data-mining tools such as latent semantic analysis (LSA). In this research perspective paper, we demonstrate the potency of using such embedded information by demonstrating that the technology acceptance model (TAM) can be reconstructed significantly by analyzing unrelated newspaper articles. We suggest that part of the reason for the phenomenal statistical validity of TAM across contexts may be related to the lexical closeness among the keywords in its measurement items. We do so not to critique TAM but to praise the quality of its methodology. Next, putting that LSA reconstruction of TAM into perspective, we show that empirical data can provide a significantly better fitting model than LSA data can. Combined, the results raise the possibility that a significant portion of variance in survey based research results from word cooccurrences in the language itself regardless of the theory or context of the study. Addressing this possibility, we suggest a method to statistically control for lexical closeness

Full counting statistics of Luttinger liquid conductor

Non-equilibrium bosonization technique is used to study current fluctuations of interacting electrons in a single-channel quantum wire representing a Luttinger liquid (LL) conductor. An exact expression for the full counting statistics of the transmitted charge is derived. It is given by Fredholm determinant of the counting operator with a time dependent scattering phase. The result has a form of counting statistics of non-interacting particles with fractional charges, induced by scattering off the boundaries between the LL wire and the non-interacting leads.Comment: 5 pages, 2 figure