Physics – Condensed Matter – Superconductivity
Scientific paper
2005-03-21
Physics
Condensed Matter
Superconductivity
3 figures
Scientific paper
10.1103/PhysRevLett.95.206807
We have fabricated a Cooper-pair transistor (CPT) with parameters such that for appropriate voltage biases, the sub-gap charge transport takes place via slow tunneling of quasiparticles that link two Josephson-coupled charge manifolds. In between the quasiparticle tunneling events, the CPT behaves essentially like a single Cooper-pair box (SCB). The effective capacitance of a SCB can be defined as the derivative of the induced charge with respect to gate voltage. This capacitance has two parts, the geometric capacitance, C_geom, and the quantum capacitance C_Q. The latter is due to the level anti-crossing caused by the Josephson coupling. It depends parametrically on the gate voltage and is dual to the Josephson inductance. Furthermore, it's magnitude may be substantially larger than C_geom. We have been able to detect C_Q in our CPT, by measuring the in-phase and quadrature rf-signal reflected from a resonant circuit in which the CPT is embedded. C_Q can be used as the basis of a charge qubit readout by placing a Cooper-pair box in such a resonant circuit.
Bladh K.
Delsing Per
Duty Tim
Gunnarsson David
Johansson Goran
No associations
LandOfFree
Observation of quantum capacitance in the Cooper-pair transistor 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 Observation of quantum capacitance in the Cooper-pair transistor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observation of quantum capacitance in the Cooper-pair transistor will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-160025