Impurities in elliptical quantum corrals

✍ Scribed by K. Hallberg; M. Nizama; J. d’Albuquerque e Castro

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 168 KB
• Volume: 39
• Category: Article
• ISSN: 0026-2692
• DOI: 10.1016/j.mejo.2008.01.041

✦ Synopsis

Elliptical quantum corrals present interesting properties due to the combination of confinement and focalizing properties. We show here that two magnetic impurities located at the foci of the systems experience an enhanced interaction, as compared to the one they would have in an open surface. These impurities interact via a superexchange AF interaction J with the surface electrons in the ellipse. For small J they are locked in a singlet state, which weakens for larger values of this parameter. When J is much larger than the hopping parameter of the electrons in the ellipse, both spins decorrelate and form a singlet with the nearest electron, thus presenting a confined RKKY-Kondo transition. We can also interpret this behavior via the entanglement or von Neumann entropy between the localized impurities and the itinerant electrons of the ellipse: for small J the entropy is nearly zero while for large J it is maximum.