1 / 9

Non-coplanar orders & phase diagram of Kagome Kondo Lattice model

Non-coplanar orders & phase diagram of Kagome Kondo Lattice model. Shivam Ghosh, Christopher L. Henley Cornell University. Pat O’ Brien, Michael Lawler Binghamton University. HFM 2014 –Cambridge U.K. Kondo Lattice Model - route to finding non-coplanar orders.

glain
Télécharger la présentation

Non-coplanar orders & phase diagram of Kagome Kondo Lattice model

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Non-coplanar orders & phase diagram of Kagome Kondo Lattice model Shivam Ghosh, Christopher L. Henley Cornell University Pat O’ Brien, Michael Lawler Binghamton University HFM 2014 –Cambridge U.K.

  2. Kondo Lattice Model - route to finding non-coplanar orders (Martin & Batista 2008 ,Akagi & Motome 2012 Chern 2010) Electrons mediate long ranged oscillatory RKKY interactions Filling (n) {Jij} (Arbitrary units) What spin order minimizes {Jij}? Is it non-coplanar?

  3. From RKKY interactions to spin orders Consider RKKY at n=1/3 Filling (n) {Jij} (arbitrary units) K But coplanar order. Other fillings? Γ √3×√3 F.T. {Jij} to get 3×3 J(q) Construct {Si} from dominant q modes

  4. Predicting spin orders in the RKKY limit Track Qopt(filling) Kagome 1st B.Z. K M Γ Γ K Γ Evolution of optimal mode connected to F.S. Qoptis insufficient to specify spin order on Kagome

  5. Monte Carlo on RKKY couplings at for all n<2/3 Diagnostics real space :4 examples of spins at different fillings (All spin directions plotted with common origin, sublattices in different color) Get a variety of non-coplanar incommensurate states! Decompose in to sublattices Spin config. mixture many Fourier modes Simplify: project on to dominant mode “Purified state”

  6. Phase diagram in the RKKY limit Smoothly evolving phases with the same broken symmetries – Classified as a single phase Incommensurate twists of Ferro locked at Q=0 Locally ferro Skyrmion textures Filling 0.18 5/12 0.2 1/3 0.59 0 0.05 0.53 “Twisted” √3×√3 √3×√3 3Q Cuboc1 (Messio2012) RKKY limit of Kondo Lattice Model gives us a variety of complex non-coplanar orders. Survive at finite JK?

  7. Variational phase diagram of the Kondo Lattice model ( comm. orders also found by - K. Barros, J. Venderbose, G.-W. Chern, and C. D. Batista, private comm.)

  8. Variational phase diagram of the Kondo Lattice model

  9. Variational phase diagram of the Kondo Lattice model Three JK dependent regimes: JK: 0-2 RKKY limit : non-coplanar incommensurate JK: 2-10 non-coplanar commensurate & incomm JK>20 DE limit: Trivial Ferromagnetic favored

More Related