Universal Detector Efficiency of a Mesoscopic Capacitor
Abstract
We investigate theoretically a novel type of high frequency quantum detector based on the mesoscopic capacitor recently realized by Gabelli et al. [Science 313, 499 (2006)SCIEAS0036-807510.1126/science.1126940], which consists of a quantum dot connected via a single channel quantum point contact to a single lead. We show that the state of a double quantum dot charge qubit capacitively coupled to this detector can be readout in the GHz frequency regime with near quantum limited efficiency. To leading order, the quantum efficiency is found to be universal owing to the universality of the charge relaxation resistance of the mesoscopic capacitor.
- Publication:
-
Physical Review Letters
- Pub Date:
- June 2009
- DOI:
- 10.1103/PhysRevLett.102.236801
- arXiv:
- arXiv:0902.0686
- Bibcode:
- 2009PhRvL.102w6801N
- Keywords:
-
- 85.35.Be;
- 73.21.La;
- 73.23.-b;
- 42.50.Dv;
- Quantum well devices;
- Quantum dots;
- Electronic transport in mesoscopic systems;
- Nonclassical states of the electromagnetic field including entangled photon states;
- quantum state engineering and measurements;
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 4 pages, 2 figures, submitted to PRL