Huang, DennisWebb, TatianaFang, ShiangSong, Can-LiChang, Cui-ZuMoodera, Jagadeesh S.Kaxiras, EfthimiosHoffman, Jenny2017-05-302016Huang, Dennis, Tatiana A. Webb, Shiang Fang, Can-Li Song, Cui-Zu Chang, Jagadeesh S. Moodera, Efthimios Kaxiras, and Jennifer E. Hoffman. 2016. “Bounds on Nanoscale Nematicity in Single-layerFeSe/SrTiO3.” Physical Review B 93 (12) (March 18). doi:10.1103/physrevb.93.125129.2469-9950http://nrs.harvard.edu/urn-3:HUL.InstRepos:32749941We use scanning tunneling microscopy (STM) and quasiparticle interference (QPI) imaging to investigate the low-energy orbital texture of single-layer FeSe/SrTiO3. We develop a T -matrix model of multiorbital QPI to disentangle scattering intensities from Fe 3dxz and 3dyz bands, enabling the use of STM as a nanoscale detection tool of nematicity. By sampling multiple spatial regions of a single-layer FeSe/SrTiO3 film, we quantitatively exclude static xz/yz orbital ordering with domain size larger than δr2 = 20 nm × 20 nm, xz/yz Fermi wave vector difference larger than δk = 0.014 π, and energy splitting larger than δE = 3.5 meV. The lack of detectable ordering pinned around defects places qualitative constraints on models of fluctuating nematicityen-USJournal Article2017-02-1420162017-05-3010.1103/PhysRevB.93.125129