Full Counting Statistics and Field Theory

We review the relations between the full counting statistics and the field theory of electric circuits. We demonstrate that for large conductances the counting statistics is determined by non-trivial saddle-point of the field. Coulomb effects in this limit are presented as quantum corrections that can stongly renormalize the action at low energies.Comment: microreview, 15 pages, accepted to Ann. Phys. (Leipzig

Spin-Flip Transistor

The recently developed semiclassical theory for magnetoelectronic circuits is applied to a transistor-like device consisting of a normal metal island and three magnetic terminals. The electric current between source and drain can be controlled by the magnetization of a ``base'' reservoir up to distances of the order of the spin-flip diffusion length.Comment: Proceedings of NATO-ARW on Semiconductor Nanostructures, 5-9 February 2001, Queenstown, NZ, to be published in Physica

Yangian of the Queer Lie Superalgebra

Take the matrix Lie superalgebra $gl_{N|N}$ with the standard generators $E_{ij}$ where $i,j=-N,...,-1,1,...,N$. Define an involutive automorphism of $gl_{N|N}$ by sending $E_{ij}$ to $E_{-i,-j}$. Then the corresponding twisted subalgebra $g$ in the polynomial current Lie superalgebra $gl_{N|N}[u]$, has a natural Lie co-superalgebra structure. Here we quantise the universal enveloping algebra $U(g)$ as a co-Poisson Hopf superalgebra. For the quantised algebra we give a description of the centre, and construct the double in the sense of Drinfeld. We also construct a class of irreducible representations of the quantised algebra, by introducing an appropriate analogue of the degenerate affine Hecke algebra.Comment: AmS-TeX, 28 pages, Section 2 streamline