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Lecture Yigal Meir

Rooster

WanneerWaar
16 april 2009 FWN-Building 5116.0124, Nijenborgh 4, 9747 AG, Groningen
Speaker: Prof. Dr. Yigal Meir
Affiliation: Physics Department - Ben-Gurion University – Beer Sheva 84105, Israel
Title: The 0.7 anomaly in quantum point contacts
Date: Thu Apr 16, 2009
Start: 15.00
Location: FWN-Building 5116.0124
Host: Caspar van der Wal
Telephone: +31 50 363 4555

Abstract

The conductance through a quantum point contact exhibits integer steps of G0 = 2e2/h. In addition, one observes an additional shoulder at a value around 0.7 G0, an observation which remained a puzzle for a couple of decades. I will discuss the history of the effect and demonstrates how the phenomenology of this "0.7 anomaly" can be fully explained in terms of a quasi-localized state, which forms as the point contact opens up. Detailed numerical calculations within spin-density functional theory indeed confirm the emergence of such a state. Quantitative calculations of the conductance and the noise are obtained using a model based on these observations, and are in excellent agreement with existing experimental observations. Lastly, the possibility of observing two-impurity Kondo physics is such a system will be discussed

Laatst gewijzigd:22 oktober 2012 14:30