Analysis of current and shot noise correlations in a double quantum dot interferometer with interdot spin interactions

Abstract

We examine an electron Aharonov-Bohm (AB) interferometer with individual quantum dots connected in parallel to macroscopic leads. Here, we focus on the effect that both inter-dot spin-spin exchange interactions and intra-dot spin flips have on the current and frequency dependent current shot noise. By appropriate control of AB magnetic flux, inter-dot Coulomb repulsion, intra-dot spin flips, and inter-dot spin-spin coupling, the probability amplitudes for the different paths of the interferometer can be controlled leading to broad tunability of both the shape and contrast of interference fringes in the current. We also show that in the shot noise at finite frequencies corresponding to the spin-spin interaction energies the noise shows pronounced super-Poissonian and sub-Poissonian structure. AB flux, which is not an integer multiple of 2π, dramatically suppresses the correlations in the shot noise.

Nonequilibirum noise spectrum and Coulomb-blockade-assisted Rabi interference in a double-dot Aharonov-Bohm interferometer

“…Nevertheless, the evaluated spectrum does show the oscillation dynamics induced by interdot transfer couplings [54]. It had also identified a pronounced super/sub-Poissonian statistics at spin-spin interaction energies [55].…”

Transient probing of the symmetry and the asymmetry of electron interference

“…46,47 The AB interference is also useful to affect the occupation difference between degenerate QDs 48 and modulate the current noises. 49,50 Various time-dependent aspects of DQD AB interferometers have been tackled. Real-time detection of interference pattern formation has been experimentally attempted.…”