title: Terahertz field control of in-plane orbital order in La(0.5)Sr(1.5)MnO4.
abstract: In-plane anisotropic ground states are ubiquitous in correlated solids such as pnictides, cuprates and manganites. They can arise from doping Mott insulators and compete with phases such as superconductivity; however, their origins are debated. Strong coupling between lattice, charge, orbital and spin degrees of freedom results in simultaneous ordering of multiple parameters, masking the mechanism that drives the transition. Here we demonstrate that the orbital domains in a manganite can be oriented by the polarization of a pulsed THz light field. Through the application of a Hubbard model, we show that domain control can be achieved by enhancing the local Coulomb interactions, which drive domain reorientation. Our results highlight the key role played by the Coulomb interaction in the control and manipulation of orbital order in the manganites and demonstrate a new way to use THz to understand and manipulate anisotropic phases in a potentially broad range of correlated materials.
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Av. Carl Friedrich Gauss 3, 08860 Castelldefels, Barcelona, Spain.
authors.forename: Timothy A
authors.identifier: http://orcid.org/0000-0002-5585-7736
authors.initials: TA
authors.lastname: Miller
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Av. Carl Friedrich Gauss 3, 08860 Castelldefels, Barcelona, Spain.|Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland.
authors.forename: Ravindra W
authors.initials: RW
authors.lastname: Chhajlany
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Av. Carl Friedrich Gauss 3, 08860 Castelldefels, Barcelona, Spain.
authors.forename: Luca
authors.initials: L
authors.lastname: Tagliacozzo
authors.affiliation: Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiation Physics, Bautzner Landstraße 400, 01328 Dresden, Germany.
authors.forename: Bertram
authors.identifier: http://orcid.org/0000-0002-7184-5620
authors.initials: B
authors.lastname: Green
authors.affiliation: Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiation Physics, Bautzner Landstraße 400, 01328 Dresden, Germany.
authors.forename: Sergey
authors.initials: S
authors.lastname: Kovalev
authors.affiliation: Department of Physics, Clarendon Laboratory, University of Oxford, Oxford OX1 3PU, UK.
authors.forename: Dharmalingam
authors.initials: D
authors.lastname: Prabhakaran
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Av. Carl Friedrich Gauss 3, 08860 Castelldefels, Barcelona, Spain.|ICREA-Institució Catalana de Recerca i Estudis Avançats, Lluís Company 23, 08010 Barcelona, Spain.
authors.forename: Maciej
authors.initials: M
authors.lastname: Lewenstein
authors.affiliation: Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiation Physics, Bautzner Landstraße 400, 01328 Dresden, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Gensch
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Av. Carl Friedrich Gauss 3, 08860 Castelldefels, Barcelona, Spain.
authors.forename: Simon
authors.identifier: http://orcid.org/0000-0002-6136-0224
authors.initials: S
authors.lastname: Wall