title: Resolving transitions in the mesoscale domain configuration in VO2 using laser speckle pattern analysis.
abstract: The configuration and evolution of coexisting mesoscopic domains with contrasting material properties are critical in creating novel functionality through emergent physical properties. However, current approaches that map the domain structure involve either spatially resolved but protracted scanning probe experiments without real time information on the domain evolution, or time resolved spectroscopic experiments lacking domain-scale spatial resolution. We demonstrate an elegant experimental technique that bridges these local and global methods, giving access to mesoscale information on domain formation and evolution at time scales orders of magnitude faster than current spatially resolved approaches. Our straightforward analysis of laser speckle patterns across the first order phase transition of VO2 can be generalized to other systems with large scale phase separation and has potential as a powerful method with both spatial and temporal resolution to study phase separation in complex materials.
authors.affiliation: 1] Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA [2] Department of Physics &Astronomy, University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: Katyayani
authors.initials: K
authors.lastname: Seal
authors.affiliation: 1] Department of Physics and Institute of Nanotechnology, Bar Ilan University, Ramat Gan 52900, Israel [2] Department of Physics and Center for Advanced Nanoscience, University of California San Diego, La Jolla, California 92093, USA.
authors.forename: Amos
authors.initials: A
authors.lastname: Sharoni
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Jamie M
authors.initials: JM
authors.lastname: Messman
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Bradley S
authors.initials: BS
authors.lastname: Lokitz
authors.affiliation: Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Shaw
authors.affiliation: Department of Physics and Center for Advanced Nanoscience, University of California San Diego, La Jolla, California 92093, USA.
authors.forename: Ivan K
authors.initials: IK
authors.lastname: Schuller
authors.affiliation: 1] Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA [2] Department of Physics &Astronomy, University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Snijders
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Thomas Z
authors.initials: TZ
authors.lastname: Ward