RTNNANO: Fundamentals of nanoelectronics

• Research unit: EU RFP
• Project number: 03.0614

Key words (English)

Quantum coherence; nanostructures; noise and fluctuations

Alternative project number (English)

EU project number: 504574

Research programs (English)

EU-programme: 6. Frame Research Programme - 2.2.1 Marie-Curie Research Training Networks

Short description (English)

See abstract

Abstract (English)

We shall investigate carrier density and current fluctuations inside chaotic cavities. Much of the existing research on quantum dots and cavities has (at best) characterized the interior in terms of a single variable such its charge, potential or distribution function. However it has long been understood that in the classical limit, a chaotic cavity connected via perfect quantum point contacts to reservoirs is noiseless. Thus with the transition from quantum scattering to classical scattering the internal state of a chaotic cavity undergoes a subtle change. Therefore we shall develop a theory that can describe the fluctuation properties of the internal state of the quantum to classical transition and explain the first experiments addressing this transition, which were recently reported. The theory will be used to investigate dephasing due to charge fluctuations. The generation of entangled electron states and their detection is a subject of high current interest. Of importance is the advancement of theoretical proposals that have a chance to be experimentally realized in the near future. We expand on recent proposals which aim at detecting entanglement in quasi-particle transport of normal electrons. Only normal contacts are used and entanglement is detected through the investigation of zero-frequency shot-noise correlators. Such proposals are similar to quantum computation schemes within purely linear optics but take advantage of the fact that quasi-particle transport occurs at the edge of a filled Fermi sea. The emphasis is on entanglement of orbital degrees of freedom, thus avoiding spin and the complication of converting spin information into charge output. Of interest in this proposal is the investigation of dephasing in such geometries due to charge fluctuations. We will advance this work in close collaboration with the teams from Leiden and Pisa.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 03.0614