KONDO EFFECT IN BILAYER GRAPHENE Diego Mastrogiuseppe, Sergio Ulloa & Nancy Sandler Department of Physics & Astronomy Ohio University, Athens, OH.

Slides:

Advertisements

Similar presentations

Ultrashort Lifetime Expansion for Resonant Inelastic X-ray Scattering Luuk Ament In collaboration with Jeroen van den Brink and Fiona Forte.

Advertisements

Probing Superconductors using Point Contact Andreev Reflection Pratap Raychaudhuri Tata Institute of Fundamental Research Mumbai Collaborators: Gap anisotropy.

D-wave superconductivity induced by short-range antiferromagnetic correlations in the Kondo lattice systems Guang-Ming Zhang Dept. of Physics, Tsinghua.

Conductance of a spin-1 QD: two-stage Kondo effect Anna Posazhennikova Institut für Theoretische Festkörperphysik, Uni Karlsruhe, Germany Les Houches,

Electronic Transport and Quantum Phase Transitions of Quantum Dots in Kondo Regime Chung-Hou Chung 1. Institut für Theorie der Kondensierten Materie Universität.

Optics on Graphene. Gate-Variable Optical Transitions in Graphene Feng Wang, Yuanbo Zhang, Chuanshan Tian, Caglar Girit, Alex Zettl, Michael Crommie,

Coulomb Blockade and Non-Fermi-Liquid Behavior in a Double-Dot Device Avraham Schiller Racah Institute of Physics Eran Lebanon (Rutgers University) Special.

A few topics in Graphene physics Antonio H. Castro Neto San Sebastian, May 2008.

Renormalised Perturbation Theory ● Motivation ● Illustration with the Anderson impurity model ● Ways of calculating the renormalised parameters ● Range.

Theory of the Quantum Mirage*

Exotic Kondo Effects and T K Enhancement in Mesoscopic Systems.

Adatoms in Graphene Antonio H. Castro Neto Trieste, August 2008.

THE STATE UNIVERSITY OF NEW JERSEY RUTGERS Studies of Antiferromagnetic Spin Fluctuations in Heavy Fermion Systems. G. Kotliar Rutgers University. Collaborators:

Magnetoresistance in oxydized Ni nanocontacts Department of Applied Physics, U. Alicante, SPAIN D. Jacob, J. Fernández-Rossier, J. J. Palacios

Quasiparticle scattering and local density of states in graphene Cristina Bena (SPhT, CEA-Saclay) with Steve Kivelson (Stanford) C. Bena et S. Kivelson,

Mott –Hubbard Transition & Thermodynamic Properties in Nanoscale Clusters. Armen Kocharian (California State University, Northridge, CA) Gayanath Fernando.

Theory of Optically Induced Magnetization Switching in GaAs:Mn J. Fernandez-Rossier, A. Núñez, M. Abolfath and A. H. MacDonald Department of Physics, University.

Is graphene a strongly correlated electron system ? Antonio H. Castro Neto Buzios, August 2008.

Nematic Electron States in Orbital Band Systems Congjun Wu, UCSD Collaborator: Wei-cheng Lee, UCSD Feb, 2009, KITP, poster Reference: W. C. Lee and C.

From Kondo and Spin Glasses to Heavy Fermions, Hidden Order and Quantum Phase Transitions A Series of Ten Lectures at XVI Training Course on Strongly Correlated.

Enhancement of Kondo effect through Rashba spin-orbit interactions. Nancy Sandler Dept. of Physics and Astronomy Ohio University In collaboration with:

Microscopic nematicity in iron superconductors Belén Valenzuela Instituto de Ciencias Materiales de Madrid (ICMM-CSIC) In collaboration with: Laura Fanfarillo.

G. S. Diniz and S. E. Ulloa Spin-orbit coupling and electronic transport in carbon nanotubes in external fields Department of Physics and Astronomy, Ohio.

Interplay of Magnetic and Superconducting Proximity effect in F/S hybrid structures Thierry Champel Collaborators: Tomas Löfwander Matthias Eschrig Institut.

MATERIALS RESEARCH NETWORK – COLLABORATIVE RESEARCH: DECOHERENCE, CORRELATIONS AND SPIN EFFECTS ON NANOSTRUCTURED MATERIALS NANCY P. SANDLER, OHIO UNIVERSITY,

Non-Fermi liquid vs (topological) Mott insulator in electronic systems with quadratic band touching in three dimensions Igor Herbut (Simon Fraser University,

Chung-Hou Chung Collaborators:

Spin polarization with a twist Nancy P. Sandler, Ohio University, DMR MWN/CIAM COLLABORATION USA-Brazil-Chile A well-known relativistic effect,

Application of the Cluster Embedding Method to Transport Through Anderson Impurities George Martins Carlos Busser Physics Department Oakland University.

2013 Hangzhou Workshop on Quantum Matter, April 22, 2013

Long Range Spatial Correlations in One- Dimensional Anderson Models Greg M. Petersen Nancy Sandler Ohio University Department of Physics and Astronomy.

Photonic Topological Insulators

F.F. Assaad. MPI-Stuttgart. Universität-Stuttgart Numerical approaches to the correlated electron problem: Quantum Monte Carlo.  The Monte.

Electronic Griffiths phases and dissipative spin liquids

Generalized Dynamical Mean - Field Theory for Strongly Correlated Systems E.Z.Kuchinskii 1, I.A. Nekrasov 1, M.V.Sadovskii 1,2 1 Institute for Electrophysics.

Wigner-Mott scaling of transport near the two-dimensional metal-insulator transition Milos Radonjic, D. Tanaskovic, V. Dobrosavljevic, K. Haule, G. Kotliar.

The design of dielectric environment for ultra long lifetime of graphene plasmon Dr. Qing Dai 22/10/2015.

Raman Scattering As a Probe of Unconventional Electron Dynamics in the Cuprates Raman Scattering As a Probe of Unconventional Electron Dynamics in the.

Collin Broholm Johns Hopkins University and NIST Center for Neutron Research Quantum Phase Transition in a Quasi-two-dimensional Frustrated Magnet M. A.

Minimal Conductivity in Bilayer Graphene József Cserti Eötvös University Department of Physics of Complex Systems International School, MCRTN’06, Keszthely,

An introduction to the theory of Carbon nanotubes A. De Martino Institut für Theoretische Physik Heinrich-Heine Universität Düsseldorf, Germany.

M.M. Asmar & S.E. Ulloa Ohio University. Outline Motivation. The studied system and the mathematical approach. Results and analysis. Conclusions.

NIRT: Building Nanospintronic and Nanomagnetic Structures: Growth, Manipulation, and Characterization at the Atomic Scale DMR Arthur R. Smith,

Www-f1.ijs.si/~bonca/work.html Cambridge, 2006 J. Bonča Physics Department, FMF, University of Ljubljana, J. Stefan Institute, Ljubljana, SLOVENIA Conductance.

Graphene: electrons in the flatland Antonio H. Castro Neto Seoul, September 2008.

2LSU(2) regime: competition between Kondo and Intermediate Valence (a numerical collaboration) George Martins Physics Department Oakland University Carlos.

Www-f1.ijs.si/~bonca/work.html New 3 SC-6, Sydney, 2007 J. Bonča Physics Department, FMF, University of Ljubljana, J. Stefan Institute, Ljubljana, SLOVENIA.

Theory of the Fano Effect and Quantum Mirage STM Spectroscopy of Magnetic Adatoms on Metallic Surfaces.

Complex magnetism of small clusters on surfaces An approach from first principles Phivos Mavropoulos IFF, Forschungszentrum Jülich Collaboration: S. Lounis,

Spin-orbit interaction in semiconductor quantum dots systems

G. S. Diniz 1, A. Latgé 2 and S. E. Ulloa 1 Spin manipulation in carbon nanotubes: All electrical spin filtering through spin-orbit interactions 1 Department.

Relation between the Anderson model and the s-d model Miyake Lab. Akiko Shiba Ref.) J. R. Schrieffer and P. A. Wolff, Phys. Rev. 149 (1966) 491.

Introduction to Chalker- Coddington Network Model Jun Ho Son.

Flat Band Nanostructures Vito Scarola

Collin Broholm Johns Hopkins University and NIST Center for Neutron Research Quantum Phase Transition in Quasi-two-dimensional Frustrated Magnet M. A.

1 The 5/2 Edge IPAM meeting on Topological Quantum Computing February 26- March 2, 2007 MPA Fisher, with Paul Fendley and Chetan Nayak Motivation: FQHE:

Tunable excitons in gated graphene systems

Power-Law Correlated Disorder in Graphene and Square Nanoribbons

Spin-orbit interaction in a dual gated InAs/GaSb quantum well

RESONANT TUNNELING IN CARBON NANOTUBE QUANTUM DOTS

Electronic properties in moiré superlattice

Materials Research Network – Collaborative Research: Decoherence, Correlations and Spin Effects on Nanostructured Materials. NSF-DMR Nancy Sandler1,

Materials Research Network – Collaborative Research: Decoherence, Correlations and Spin Effects on Nanostructured Materials. NSF-DMR Nancy Sandler1,

Bumsoo Kyung, Vasyl Hankevych, and André-Marie Tremblay

Conductance through coupled quantum dots

PHY 745 Group Theory 11-11:50 AM MWF Olin 102 Plan for Lecture 30:

Conductance through coupled quantum dots

Persistent spin current

Nonlinear response of gated graphene in a strong radiation field

Boundary Conformal Field Theory & Nano-structures

Presentation transcript:

KONDO EFFECT IN BILAYER GRAPHENE Diego Mastrogiuseppe, Sergio Ulloa & Nancy Sandler Department of Physics & Astronomy Ohio University, Athens, OH

Kondo effect in a simple metal Anderson model Schrieffer-Wolff transformation Kondo model Crossover between free spin behavior and entanglement between impurity spin and conduction electrons

Motivation D. Withoff and E. Fradkin, PRL 64, 1835 (1990) K. Ingersent, PRB 54, (1996) needed for Kondo regime Pseudogap Kondo effect in single layer graphene M. Hentschel M. and F. Guinea, PRB, 76 (2007) B. Dora and P. Thalmeier, PRB 76, (2007) K. Sengupta and G. Baskaran, PRB 77, (2008) P. Cornaglia et al, PRL 102, (2009) Z-G Zhu et al, EPL 90, (2010) T. O. Wehling et al, PRB 81, (2010) B. Uchoa et al, PRL 106, (2011) Kondo in graphene Image: A. Castro Neto et al, RMP 81,109 (2009)

Motivation (unpublished) Kondo effect in single layer graphene Kondo effect in bilayer graphene

Bilayer graphene – band structure Bernal stacking A1 B1 Feature in DOS at B2 A2

Addition of the impurity

Schrieffer-Wolff transformation With a suitable choice of S to first order in V Anderson model for bilayer Kondo model band electronsimpurity hybridization

Results Diagonalizing (and for ) Two effective channels coupled to the impurity, but no possibility of 2-channel Kondo two eigenvalues are 0 and We are going to concentrate in

Half filling Reduces to effective single layer problem For the impurity in the middle of the hexagon, J = 0 T. O. Wehling et al, PRB 81, (2010) B. Uchoa et al, PRL 106, (2011) The result is insensitive to the relationship in

Away from half-filling Problem with SW tranformation Possible issues (work in progress): We get closer to the jump in DOS Interband scattering induced by impurity (is charge well defined?) May higher order commutators in SW regularize the divergences?

Conclusions Two effective channels coupled to the impurity (FM, AFM). No possibility of two-channel Kondo. Quadratic bands at half filling, no need of a critical J for having Kondo. At half-filling the results reduce to an effective single layer problem. Away from half filling, problem with SW transformation (jump in DOS, interband scattering, higher order terms in SW).