Counting interacting electrons in one dimension

RWTH Publications (RWTH Aachen)

Abstract

The calculation of the full counting statistics of the charge within a finite interval of an interacting one-dimensional system of electrons is a fundamental, yet as of now unresolved problem. Even in the non-interacting case, charge counting turns out to be more difficult than anticipated because it necessitates the calculation of a nontrivial determinant and requires regularization. Moreover, interactions in a one-dimensional system are best described using bosonization. However, this technique rests on a long-wavelength approximation and is a priori inapplicable for charge counting due to the sharp boundaries of the counting interval. To mitigate these problems, we investigate the counting statistics using several complementary approaches. To treat interactions, we develop a diagrammatic approach in the fermionic basis, which makes it possible to obtain the cumulant generating function up to arbitrary order in the interaction strength. Importantly, our formalism preserves charge quantization in every perturbative order. We derive an exact expression for the noise and analyze its interaction-dependent logarithmic cutoff. We compare our fermionic formalism with the results obtained by other methods, such as the Wigner crystal approach and numerical calculations using the density-matrix renormalization group. Surprisingly, we show good qualitative agreement with the Wigner crystal for weak interactions, where the latter is in principle not expected to apply.

Authors 5

1. Oleksiy Kashuba

   Forschungszentrum Jülich

   Affiliation as printed

   Peter Grünberg Institute , Theoretical Nanoelectronics , Forschungszentrum Jülich , D-52425 Jülich , Germany

2. Thomas L. Schmidt

   University of Luxembourg · Victoria University of Wellington

   Affiliation as printed

   Department of Physics and Materials Science , University of Luxembourg , L-1511 Luxembourg , Luxembourg

   School of Chemical and Physical Sciences , Victoria University of Wellington , P.O. Box 600 , Wellington 6140 , New Zealand

3. Fabian Hassler Aachen Institute for Quantum Information

   RWTH Aachen University

   Affiliation as printed

   Institute for Quantum Information , RWTH Aachen University , 52056 Aachen , Germany

4. Andreas Haller

   University of Luxembourg

   Affiliation as printed

   Department of Physics and Materials Science , University of Luxembourg , L-1511 Luxembourg , Luxembourg

5. Roman P. Riwar

   Forschungszentrum Jülich

   Affiliation as printed

   Peter Grünberg Institute , Theoretical Nanoelectronics , Forschungszentrum Jülich , D-52425 Jülich , Germany