Institut de Chimie Moléculaire et des Matériaux d'Orsay

Synthèse, Propriétés & Modélisation des Matériaux - SP2M

Matériaux fonctionnels

Notre groupe est composé de trois professeurs (Nita Dragoe, Loreynne Pinsard-Gaudart et Patrick Berthet) ; un professeur émérite (Alexandre Revcolevschi) ; quatre maitres de conférences (David Bérardan, Claudia Decorse, Raphaël Haumont et Nghi Pham) ; un ingénieur d’étude (Romuald Saint-Martin) et une assistante ingénieur (Céline BYL).


Low-Dimensional cuprates

Initiated by the discovery of high-Tc superconductivity in cuprate compounds, there is a renewed and growing interest in the electronic and magnetic properties of one- and two-Dimensional (1D and 2D) structures. The enormous interest in the physics of these magnetic systems is due to a variety of ground states such as spin-gap, spin-Peierls, and spin-liquid states that these systems exhibit. In particular, S = ½ Heisenberg antiferromagnetic (HAF) systems with the magnetic interactions giving rise to a chain, ladder or plane topology have been considered recently.

In our team, the investigated materials are the low dimensional cuprates Sr2CuO3 -considered to be the model system of strongly anisotropic spin-1/2 Heisenberg antiferromagnets-, SrCuO2 and (La,Sr,Ca)14Cu24O41 exhibiting in their structures an alignment of Cu2+ ions of spin ½ as linear chains or ladders, showing thus a distinct 1D character. In order to obtain a better understanding of the physics of spin-chains and spin-ladders, the influence of the purity of the compounds and also of doping on the copper site (Mg2+, Zn2+, Ni2+, Co2+) is investigated.

Most of the time, single crystals are required. In order to realize physical measurements in the best conditions, perfect homogeneous single crystals of excellent quality were synthesized by the Travelling Solvent Zone Method .

Collaborative partners

  • IFW, Dresden, Germany : Anisotropic thermal conductivity

  • CSNSM, Université Paris-Sud : ARPES (detailed electronic structure)

  • University of Groningen : Spin-seebeck effect

  • University of Cyprus : Thin film deposition