Accession Number : AD1024294


Title :   Optical Spectroscopy and Imaging of Correlated Spin Orbit Phases


Descriptive Note : Technical Report,15 Mar 2013,14 Mar 2016


Corporate Author : California Institute of Technology Pasadena United States


Personal Author(s) : Hsieh,David


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1024294.pdf


Report Date : 14 Jun 2016


Pagination or Media Count : 18


Abstract : Over the course of this ARO award we constructed three ultrafast laser based probes (nonlinear optical rotational anisotropy, nonlinear optical microscopy and time-resolved optical reflectivity) to search for novel electronic phases in correlated electron materials. Using these techniques, we completed five major scientific projects. 1) We discovered previously unresolved oxygen sub-lattice distortions in layered perovskite iridates, which explain the anomalous magneto-elastic coupling and basal plane ferromagnetism observed in Sr2IrO4 and Sr3Ir2O7 respectively. 2) We discovered a previously hidden odd-parity magnetic order in the pseudogap region of hole-doped Sr2IrO4, which is consistent with the long-sought orbital loop-current phase that has been conjectured to underlie the pseudogap region of the cuprate high-Tc superconductors. 3) We discovered a similar odd-parity magnetic order in the pseudogap region of hole-doped YBa2Cu3O7 that appears to terminate at a quantum critical point inside the superconducting dome. 4) We discovered an ultrafast photo-induced insulator-to-metal phase transition in Ca2RuO4 that, unlike the phase transition in thermal equilibrium, is not accompanied by any structural distortion. 5) We revealed the weak Mott insulating character of Sr3Ir2O7 and discovered the emergence of an unconventional density wave instability upon electron-doping that is reminiscent of the charge ordering recently reported in under-doped cuprates.


Descriptors :   Anisotropy , Microscopy , reflectivity , nonlinear optics


Subject Categories : Crystallography


Distribution Statement : APPROVED FOR PUBLIC RELEASE