ANR LoMaCoCuP

Local manipulation of collective quantum processes in correlated electronic states

2008-2010

Participants:
  • Institut Néel/CNRS-UJF, Grenoble (P. Monceau)
  • LPMC, Univesrity of Picardy, Amiens (I. Lukyanchuk)
  • Laboratoire de Physique des Solides, Université Paris-Sud (N. Kirova)
  • Laboratoire de Physique Théorique , Université Paris-Sud (S. Brazovsky)

The project focuses on fundamental aspects of creation, manipulation and study of fabricated or spontaneous nano-scale low-dimensional electronic structures. The major idea is to explore local transformations of various degenerate ground states, which are formed due to a spontaneous breaking of the initial electronic liquid symmetry. Particularly appealing are the electronic crystals, formed by spontaneous spatial aggregations of electrons. Their most accessible forms are the charge density waves in compounds composed with weakly interacting chains or layers. Various driving forces, such as charge injection, field effect doping or surface strain, can easily influence their ground state. Electronic crystals can form solitonic lattices, dislocations and their arrays. The important advantage of such structures with respect to prefabricated devices, is the possibility of reversible manipulation by the electric and magnetic field.

Long experience of initiation and/or exploration of leading edge techniques (focused ion beam fabrication - FIB - of overlap junctions, space resolved and microscopic X-ray diffraction, high magnetic fields, theory of local nonlinear electronic processes) allows for the Project team to plan the following objectives of research:

-Intrinsic tunneling spectroscopy in layered charge/spin density wave systems, in magnetic superconductors and in graphene.

-Effect of a high magnetic field (up to 60T) in the ground state of electronic crystals. Search for field-induced phase transition in electronic crystals and graphene     

-Determination of topological defects in Electronic Crystals by coherent micrometer X-Ray at the ESRF and/or SOLEIL

-Mesoscopic properties of charge density waves systems and graphene-based devices. Coherent quantum effects in electronic crystals.  

-Theoretical works on spontaneous symmetry breaking degenerate ground states, collective modes, topological objects and their superstructures, kinetics and dynamics of solitons in application to low dimensionality and confined geometry of devices and materials to be explored.