Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2006-09-10
Phys. Rev. B 75, 045332 (2007)
Physics
Condensed Matter
Strongly Correlated Electrons
11 pages, 5 figures. Revised version, references and technical details added, typos corrected
Scientific paper
10.1103/PhysRevB.75.045332
The electrical current noise of a quantum wire is expected to increase with increasing applied voltage. We show that this intuition can be wrong. Specifically, we consider a single channel quantum wire with impurities and with a capacitive coupling to nearby metallic gates and find that its excess noise, defined as the change in the noise caused by the finite voltage, can be negative at zero temperature. This feature is present both for large ($c \gg c_q$) and small ($c \ll c_q$) capacitive coupling, where $c$ is the geometrical and $c_q$ the quantum capacitance of the wire. In particular, for $c \gg c_q$, negativity of the excess noise can occur at finite frequency when the transmission coefficients are energy dependent, i.e. in the presence of Fabry-P\'erot resonances or band curvature. In the opposite regime $c \lesssim c_q$, a non trivial voltage dependence of the noise arises even for energy independent transmission coefficients: at zero frequency the noise decreases with voltage as a power law when $c < c_q/3$, while, at finite frequency, regions of negative excess noise are present due to Andreev-type resonances.
Dolcini Fabrizio
Grabert Hermann
Safi Imen
Trauzettel Björn
No associations
LandOfFree
Negativity of the excess noise in a quantum wire capacitively coupled to a gate does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Negativity of the excess noise in a quantum wire capacitively coupled to a gate, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Negativity of the excess noise in a quantum wire capacitively coupled to a gate will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-658325