Measurement Back-Action in Quantum Point-Contact Charge Sensing
AbstractCharge sensing with quantum point-contacts (QPCs) is a technique widely used in semiconductor quantum-dot research. Understanding the physics of this measurement process, as well as finding ways of suppressing unwanted measurement back-action, are therefore both desirable. In this article, we present experimental studies targeting these two goals. Firstly, we measure the effect of a QPC on electron tunneling between two InAs quantum dots, and show that a model based on the QPC’s shot-noise can account for it. Secondly, we discuss the possibility of lowering the measurement current (and thus the back-action) used for charge sensing by correlating the signals of two independent measurement channels. The performance of this method is tested in a typical experimental setup. View Full-Text
Share & Cite This Article
Küng, B.; Gustavsson, S.; Choi, T.; Shorubalko, I.; Pfäffli, O.; Hassler, F.; Blatter, G.; Reinwald, M.; Wegscheider, W.; Schön, S.; Ihn, T.; Ensslin, K. Measurement Back-Action in Quantum Point-Contact Charge Sensing. Entropy 2010, 12, 1721-1732.
Küng B, Gustavsson S, Choi T, Shorubalko I, Pfäffli O, Hassler F, Blatter G, Reinwald M, Wegscheider W, Schön S, Ihn T, Ensslin K. Measurement Back-Action in Quantum Point-Contact Charge Sensing. Entropy. 2010; 12(7):1721-1732.Chicago/Turabian Style
Küng, Bruno; Gustavsson, Simon; Choi, Theodore; Shorubalko, Ivan; Pfäffli, Oliver; Hassler, Fabian; Blatter, Gianni; Reinwald, Matthias; Wegscheider, Werner; Schön, Silke; Ihn, Thomas; Ensslin, Klaus. 2010. "Measurement Back-Action in Quantum Point-Contact Charge Sensing." Entropy 12, no. 7: 1721-1732.