PROCEEDINGS:  Journal de Physique IV,  v. 9, Pr10, December 1999.
 
 
 

ECRYS-99: The Concept.
The workshop is intended to link  subjects of Density Waves in low dimensional conductors with other flexible crystalline states: 3D and 2D  Wigner Crystals, Charge Ordering in doped oxides including Stripes Phases, etc. The topic of Electronic Crystals  embraces numerous cases of spontaneous structural aggregation of electrons in solids. Depending on Coulomb interactions, the lattice deformations involvement, spin ordering and the dimensionality, the Electronic Crystals  acquire forms  of the Charge- and Spin- Density Waves or of interface 2D Wigner crystals. Special realizations of these states are observed in high magnetic fields. The new family members are the Charge Ordered phases in doped oxides. While microscopic grounds may be essentially different and are very rich in their diversity, the collective properties are remarkably universal embracing also such extensively studied system as  Vortex Lattices and other flexible structures, e.g. Magnetic Bubbles or Charged Liquid Suspensions.
Having a long history of theoretical predictions, Electronic Crystals became the subject of experimental studies nearly 25 years ago since the discovery of Charge Density Waves in quasi one-dimensional conductors. They were associated with spontaneous superlattice structures, with a variety of nonlinear and nonstationary effects due to the collective sliding. The discovery of Spin Density Waves in organic metals brought new features due to high magnetic field effects, to their exceptional purity and to specific NMR facilities. Later the Wigner crystals became a hot subject in studies of 2d electron gas at heterojunctions. Also the earliest type of  Wigner crystals - electrons at liquid helium surface, demonstrated their collective properties. Other relevant objects are the crystalline forms of charged liquid suspensions, arrays of magnetic bubbles and finally the vortex lattices especially in layered superconductors. New common topics in studies of all Electronic Crystals and Vortex Lattices are the glass states, quantum and mesoscopic effects at low temperatures, contact effects and plastic flows: the transport and the current conversion via phase slips, dislocations and vacancies.
Six years ago the state of the art has been reviewed at the first workshop ECRYS-93 in France which was attended by most of the key participants in the field. The subject of the Charge Density Waves alone have been presented, once again in France, at the NATO school Les Houches 95. Meanwhile a further development through 90's calls for a new meeting of the community. At the ECRYS-99 we are planning to discuss both particular realizations of Electronic Crystals  and the common issues related to sliding, pinning, contact strains, plasticity, phase slips, glassy state, etc. We shall include new specific discoveries and particular  mechanisms: X-ray holography of local effects in alloys, synchrotron radiation and other space resolved accesses to contact effects and to the current conversion problem, quantum mesoscopics of the sliding state in magnetic fields, spin breakdown in HMFs and related issues of soliton physics, stripe phases, problems  of pseudo gaps and of electronic interactions in view of studies by optics and ARPES, etc.