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.

 

 

Latest events

province:

Jean-Bernard Bru (UPV/EHU, IKERBASQUE) (Seminar)

When end where

11/2010

Description

2009/12/18,   Jean-Bernard Bru (UPV/EHU, IKERBASQUE)

Place: Sala de Seminarios del Departamento de Física Teórica e Historia de la Ciencia
Time: 12h.
Title: Effect of a Locally Repulsive Interaction on s-wave Superconductors


Abstract
In collaboration with W. de Siqueira Pedra, we analyze the thermodynamic impact of the Coulomb repulsion on s-wave superconductors via a rigorous study of equilibrium and ground states of the strong coupling BCS-Hubbard Hamiltonian. I will explain that the one-site electron repulsion can favor superconductivity at fixed chemical potential by increasing the critical temperature and/or the Cooper pair condensate density. The Meissner effect is also shown to be rather generic but I will also discuss the feasibility of coexistence of superconducting and ferromagnetic phases, for instance near half-filling and at strong repulsion. Additionnally, our proof of a superconductor-Mott insulator phase transition implies a rigorous explanation of the necessity of doping insulators to create superconductors.