About QUINST

Quantum mechanics is at the heart of our technology and economy - the laser and the transistor are quantum devices - but its full potential is far from being realized. Recent technological advances in optics, nanoscience and engineering allow experimentalists to create artificial structures or put microscopic and mesoscopic systems under new manipulable conditions in which quantum phenomena play a fundamental role.

Quantum technologies exploit these effects with practical purposes. The objective of Quantum Science is to discover, study, and control quantum efects at a fundamental level. These are two sides of a virtuous circle: new technologies lead to the discovery and study of new phenomena that will lead to new technologies.

Our group's aim is  to control and understand quantum phenomena in a multidisciplinary intersection of  Quantum Information, Quantum optics and cold atoms, Quantum Control, Spintronics, Quantum metrology, Atom interferometry, Superconducting qubits and Circuit QED and Foundations of Quantum Mechanics.

 

 

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Prof. Roland Winkler (Seminar)

When end where

12/2012

Description

2011/11/25, Prof. Roland Winkler


Place:  Sala de Seminarios del Departamento de Física Teórica e Historia de la Ciencia
Time: 12h
Title: Oscillatory multiband dynamics of free particles: The ubiquity of zitterbewegung effects
 
 
Abstract
  In the Dirac theory for the motion of free relativistic electrons,
highly oscillatory components appear in the time evolution of
physical observables such as position, velocity, and spin angular
momentum. This effect known as zitterbewegung (German for quivering
motion) is commonly considered to be a quirk of the otherwise very
successful Dirac theory of relativistic electron dynamics. Its
physical significance has been discussed controversially over the
years.

I will demonstrate that rather different solid-state systems with
gapped and/or spin-split energy spectrum exhibit analogs of
zitterbewegung as a common feature. It is also shown that many
features of zitterbewegung are shared by the simple and well-known
Landau Hamiltonian describing the dynamics of two-dimensional
electron systems in the presence of a magnetic field perpendicular
to the plane.

I will review various aspects of Zitterbewegung phenomena and link
the latter with observable effects such as electric-field-controllable spin precession and spin-dependent magnetic focusing.