Speaker
Adrian Gozar
(Brookhaven National Laboratory)
Description
Adrian Gozar
Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
Christopher Homes
Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
Girsh Blumberg
Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
Verner Thorsmolle
Laboratory for Quantum Magnetism, Ecole Polytechnique Federale de Lausanne (EPFL), CH-101 Switzerland
Henrik Ronnow
Laboratory for Quantum Magnetism, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Switzerland
The terahertz (THz) excitations in the quantum spin-ladder system Sr14Cu24O41 have been determined along the c-axis using infrared, Raman and THz time-domain spectroscopy. Low-frequency infrared and Raman active modes are observed above and below the charge-ordering temperature T_co ~ 200 K over the narrow interval of 1 - 2 meV. A new infrared mode around 1 meV develops below 100 K. The temperature dependence of these modes shows that they are coupled to the charge- and spin-density-wave correlations in this system. These low-energy features are conjectured to originate in the gapped sliding-motion of the chain and ladder sub-systems, which are both incommensurate and charged.
Primary author
Adrian Gozar
(Brookhaven National Laboratory)
