• Submit to Entropy Login Register
• MDPI
• Journals A-Z
• For Authors
• For Editors
• About
• Open Access Policy

• Abstract
• Full-Text PDF [1597 KB]

• Article Statistics
• Google Scholar
• Order Reprints

• Cite this article
• Export to BibTeX
• Export to EndNote

• [+] on DOAJ
• Küng, B
• Gustavsson, S
• Choi, T
• Shorubalko, I
• Pfäffli, O
• Hassler, F
• Blatter, G
• Reinwald, M
• Wegscheider, W
• Schön, S
• Ihn, T
• Ensslin, K
• [+] on Google Scholar
• Küng, B
• Gustavsson, S
• Choi, T
• Shorubalko, I
• Pfäffli, O
• Hassler, F
• Blatter, G
• Reinwald, M
• Wegscheider, W
• Schön, S
• Ihn, T
• Ensslin, K
• [+] on PubMed
• Küng, B
• Gustavsson, S
• Choi, T
• Shorubalko, I
• Pfäffli, O
• Hassler, F
• Blatter, G
• Reinwald, M
• Wegscheider, W
• Schön, S
• Ihn, T
• Ensslin, K

•  CiteULike
•  Facebook
•  Mendeley
•  Twitter

This article is

• freely available
• re-usable

Entropy 2010, 12(7), 1721-1732; doi:10.3390/e12071721

Article

Measurement Back-Action in Quantum Point-Contact Charge Sensing

Bruno Küng ^1,* , Simon Gustavsson ^1,2 , Theodore Choi ¹ , Ivan Shorubalko ^1,3 , Oliver Pfäffli ¹ , Fabian Hassler ^4,5 , Gianni Blatter ⁴ , Matthias Reinwald ⁶ , Werner Wegscheider ^1,6 , Silke Schön ⁷ , Thomas Ihn ¹  and Klaus Ensslin ¹

¹ Solid State Physics Laboratory, ETH Zurich, Schafmattstr. 16, 8093 Zurich, Switzerland ² Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA ³ EMPA, 8600 Dübendorf, Switzerland ⁴ Theoretische Physik, ETH Zurich, Wolfgang-Pauli-Str. 27, 8093 Zurich, Switzerland ⁵ Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, The Netherlands ⁶ Institut für Experimentelle und Angewandte Physik, Universität Regensburg, 93040 Regensburg, Germany ⁷ FIRST Laboratory, ETH Zurich, Wolfgang-Pauli-Str. 10, 8093 Zurich, Switzerland

* Author to whom correspondence should be addressed.

Received: 10 May 2010; in revised form: 21 June 2010 / Accepted: 25 June 2010 / Published: 29 June 2010

(This article belongs to the Special Issue Quantum Information)

Download PDF Full-Text [1597 KB, uploaded 29 June 2010 11:46 CEST]

Abstract: Charge 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.

Keywords: quantum dots; quantum wires; noise; single-electron tunneling

Article Statistics

Cite This Article