Fig. 1: Mott nano-textures in a bilayer ruthenate.
From: Nano-imaging of strain-tuned stripe textures in a Mott crystal
a Schematic depiction of a 100 micron-scale thin Ca3(Ti0.1Ru0.9)2O7 crystal mounted to a home-built strain stage inside the low-temperature nanoscope. b Crystal structure of the bilayer ruthenate; our experiments apply uniaxial strain within 30 degrees of the crystallographic b-axis. c Metal/insulator nano-textures are detected by nano-imaging the crystal surface (ab-plane) at 100 meV probing energy during in situ application of strain. d Striped nanotextures emerging while cooling the crystal from the metallic L phase through the Mott transition from T = 95.5 K to 94.5 K without applied external strain; images shown were acquired at \(\approx\)0.3 K intervals. e Minority phases take the form of acicular domains; topography shares color scale with f. f Correlative topography, contact potential difference \(\Delta \Phi\) (see text) and nano-IR signal \(\sigma\) recorded across of a series of L phase domains; the color-scale for \(\sigma\) indicates the nano-IR response from the insulating phase is 30% that of the metal. g Correlative line-profiles along the arrow in (f) associated with each imaging channel; the surface work function anticorrelates local metallicity, and expansion of L domains buckles the surface topography. h Same region as (d) imaged while warming from the insulating L phase; images shown were acquired at \(\approx\)0.3 K intervals. i Inferred schematic structure of coexisting L and S domains ([011] habit plane) showing associated RuO6 octahedral deformations.
