Consider a mesoscopic system connected to two reservoirs. Mesoscopic objects are so small that fluctuations around the average properties (current, charge) become significant. Here we characterize these fluctuations by computing the current-current correlation function and its Fourier transform: the noise spectrum.

The talk presents our results for two single level quantum dots connected in parallel. Considering the dots in the Coulomb blockade regime, we are able to calculate analytically the noise spectra of this structure for a finite bias, a finite temperature, and with an Aharonov-Bohm (AB) flux.

At finite frequencies the noise spectrum is very sensitive to where the currents are monitored. Therefore, we calculate the noise for different choices of the currents: the auto- and cross-correlations are calculated for currents in the same or in different leads, respectively.

At zero temperature and without bias there are 2 steps at the noise spectra, at frequencies that correspond to the dots resonance levels, and when the resonance levels are at opposite sides relative to the Fermi energy there is a dip at a frequency that correspond to the difference between the two levels. This dip appears both in the auto- and in the cross-correlation noise, but it oscillates with the AB flux only in the latter. A finite bias can split each step in the noise spectra into 2 or 4 steps, new dips may appear, and dips may turn into peaks as the bias voltage is increased. A finite temperature smears the steps, but it can also give rise to new dips at certain frequencies.

By first analyzing the single dot case [1], we are able to identify the dips and peaks in the noise spectra that are due to the interference between the dots. These phenomena will be the main topic of the talk.

[1] E, A. Rothstein, O. Entin-Wohlman, and A. Aharony, Phys. Rev. B 79, 075307 (2009).