Showing papers by "Yoseph Imry published in 2006"
TL;DR: General quantum restrictions on the noise performance of linear transistor amplifiers are used to identify the region in parameter space where the quantum-limited performance is achievable and to construct a practical procedure for approaching it experimentally using only the knowledge of directly measurable quantities.
Abstract: General quantum restrictions on the noise performance of linear transistor amplifiers are used to identify the region in parameter space where the quantum-limited performance is achievable and to construct a practical procedure for approaching it experimentally using only the knowledge of directly measurable quantities: the gain, (differential) conductance, and the output noise. A specific example of resonant barrier transistors is discussed.
3 citations
01 Jan 2006
TL;DR: In this article, the authors discussed measurements of the resonant quantum transmission amplitude tQD = −i|tQD|e iαQD through a quantum dot (QD) through a Mesoscopic solid state Aharonov-Bohm interferometers (ABIs) as function of the plunger gate voltage V.
Abstract: Summary. We discuss measurements of the resonant quantum transmission amplitude tQD = −i|tQD|e iαQD through a quantum dot (QD), as function of the plunger gate voltage V . Mesoscopic solid state Aharonov-Bohm interferometers (ABIs) have been used to measure the “intrinsic” phase, αQD, when the QD is placed on one of the paths. In a “closed” interferometer, connected to two terminals, the conductance G = 2e 2 h |tQD| 2 through the ABI is an even function of the magnetic flux Φ = � cφ/e threading the ABI ring. Therefore, fits of G to the 2-slit formula A + B cos(φ + β) allow only jumps of β between 0 and π. Here we include the many reflections of the electrons within the ABI ring, and replace the 2-slit formula by a new formula, which allows to extract both |tQD| and αQD from the closed ABI data. Also, the relation |tQD| 2 ∝ sin 2 (αQD) allows a direct measurement of αQD(V ), without interferometry.