Search for incipient lattice instabilities inMgB2by anelastic spectroscopy

Anelastic spectroscopy studies of high-Tc superconductors

Two families of cuprates exhibiting high-Tc superconductivity, YBa2Cu3O6+x (YBCO) and La2xSrxCuO4+δ (LSCO), have been extensively studied by anelastic spectroscopy, by measuring the complex dynamic Young’s modulus E (ω, T ) = E′ + iE′′ of ceramic samples at frequencies of 0.5-20 kHz between 1 and 900 K. Results are also presented on oxygen vacancies in the ruthenocuprate RuSr2GdCu2O8−δ. The ela...

Lattice instabilities in bulk EuTiO3

Lattice instabilities in bulk EuTiO3 D. Bessas,1,2,* K. Z. Rushchanskii,3 M. Kachlik,4 S. Disch,1,5 O. Gourdon,6,7,† J. Bednarcik,8 K. Maca,4 I. Sergueev,1,9,‡ S. Kamba,10 M. Ležaić,3 and R. P. Hermann1,2,§ 1Jülich Centre for Neutron Science JCNS and Peter Grünberg Institut PGI, JARA-FIT, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany 2Faculté des Sciences, Université de Liège, B-4000 L...

Theoretical study of lattice instabilities in YBa2Cu3O7.

Vortex Lattice Instabilities in YBa2Cu3O7-x Nanowires

High-resolution focused ion beam lithography has been used to fabricate YBa₂Cu₃O7-x (YBCO) wires with nanometric lateral dimensions. In the present work, we investigate Flux-flow instabilities in nanowires of different widths, showing sudden voltage switching jumps from the superconducting to the normal state. We present an extensive study on the temperature and field dependence of the switchin...

Incipient quantum melting of the one–dimensional Wigner lattice

A one–dimensional tight–binding model of electrons with long–range Coulomb interactions is studied in the limit where double site occupancy is forbidden and the Coulomb coupling strength V is large with respect to the hopping amplitude t. The quantum problem of a kink–antikink pair generated in the Wigner lattice (the classical ground state for t = 0) is solved for fillings n = 1/s, where s is ...