Joerg Schmalian
 Professor - Iowa State University

Senior Physicist - Ames Lab - USDOE


 

Contact information

A 513 Zaffarano Hall
Department of Physics and Astronomy
Iowa State University
Ames, Iowa 50011


 

RESEARCH INTERESTS

RESEARCH HIGHLIGHTS

We investigate the emergence of superconductivity in doped or pressurized Mott insulators within the framework of resonating valence bond states, where strong quantum fluctuations of frustrated spins lead to unconventional pairing, superconductivity and new inhomogeneous states. We find spin liquid behavior  and d-wave superconductivity in an organic charge transfer salt as function of the interaction strength. We also predict superconductivity upon hole doping of the Mott insulating valence bond solid SrCu2(BO3)2 while no superconductivity is expected for electron doping. Superconductivity in the hole doped system is not(!) due to a delocalization of existing singlets in the valence bond solid and is closely related to a spontaneous emergence of inhomogeneous plaquette order.

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J. Liu, J. Schmalian, N. Trivedi, Pairing and Superconductivity Driven by Strong Quasiparticle Renormalization in Two-Dimensional Organic Charge Transfer Salts Phys. Rev. Lett 94, 127003 (2005).

J. Liu, N. Trivedi, Y. Lee, B. N. Harmon, J. Schmalian,  Quantum Phases in a Doped Mott Insulator on the Shastry-Sutherland Lattice,  Phys. Rev. Lett. 99, 227003 (2007)

 

We show that the emergent relativistic symmetry of electrons in graphene near its quantum critical point  implies a crucial importance of the Coulomb interaction. We derive scaling laws, valid near the quantum critical point, that dictate the nontrivial magnetic and charge response of interacting graphene. Our analysis yields numerous predictions for how the Coulomb interaction will be manifested in experimental observables such as the diamagnetic response and electronic compressibility.

D. E. Sheehy, J. Schmalian,  Quantum Critical Scaling in Graphene, Phys. Rev. Lett. 99, 226803 (2007).

 

We present a theory for superconductivity and charge Kondo fluctuations, i.e., resonant quantum valence fluctuations by two charge units, for Tl-doped PbTe. We show that Tl is very special as it first supplies a certain amount of charge carriers to the PbTe-valence band and then puts itself into a self-tuned resonant state to yield a new, robust pairing mechanism for these carriers.

  

M. Dzero and J. Schmalian,  Superconductivity in Charge Kondo Systems, Phys. Rev. Lett. 94, 157003 (2005).

see also the related experimental paper: Y. Matsushita, H. Bluhm, T. H. Geballe, and I. R. Fisher , Evidence for Charge Kondo Effect in Superconducting Tl-Doped PbTe,  Phys. Rev. Lett.  94, 157003 (2005).

The cooperative rearrangement of groups of many molecules has long been thought to underlie the dramatic slowing of liquid dynamics on cooling towards the glassy state. For instance, there exists experimental evidence for cooperatively rearranging regions (CRRs) on the nanometre length scale near the glass transition. The random first-order transition (RFOT) theory of glasses predicts that, near the glass-transition temperature, these regions are compact, but computer simulations and experiments on colloids suggest CRRs are string-like. Here, we present a microscopic theory within the framework of RFOT, which unites the two situations. We show that the shapes of CRRs in glassy liquids should change from being compact at low temperatures to fractal or 'stringy' as the dynamical crossover temperature from activated to collisional transport is approached from below. This theory predicts a correlation of the ratio of the dynamical crossover temperature to the laboratory glass-transition temperature, and the heat-capacity discontinuity at the glass transition. The predicted correlation quantitatively agrees with experimental results for 21 materials.

J. D. Stevenson, J. Schmalian, P. G. Wolynes The shapes of cooperatively rearranging regions in glass-forming liquids, Nature-Physics 4 268 (2006).

We show that the interplay of geometric criticality and quantum fluctuations leads to a novel universality class for the percolation quantum phase transition in diluted magnets. All critical exponents involving dynamical correlations are different from the classical percolation values, but in two dimensions they can nonetheless be determined exactly. We develop a complete scaling theory of this transition, and we relate it to recent experiments in La2Cu1-p(Zn,Mg)pO4. Our results are also relevant for disordered interacting boson systems.

 

T. Vojta and J. Schmalian, Percolation Quantum Phase Transitions in Diluted Magnets, Phys. Rev. Lett. 95, 237206 (2005).


PERSONAL HISTORY 
HONORS AND AWARDS  

PH. D. STUDENTS

 

POSTDOCS

 PUBLICATIONS 
  1. D. E. Sheehy, J. Schmalian, Quantum Critical Scaling in Graphene, Phys. Rev. Lett. 99, 226803 (2007).

  2. J. Liu, N. Trivedi, Y. Lee, B. N. Harmon, J. Schmalian, Quantum Phases in a Doped Mott Insulator on the Shastry-Sutherland Lattice, Phys. Rev. Lett. 99, 227003 (2007)

  3. C. D. Batista, J. Schmalian, N. Kawashima, P. Sengupta, S. E. Sebastian, N. Harrison, M. Jaime, and I. R. Fisher, Geometric Frustration and Dimensional Reduction at a Quantum Critical Point, Phys. Rev. Lett. 98, 257201 (2007).

  4.  M. Dzero, M. R. Norman, I. Paul, C. Pepin, J. Schmalian, Quantum critical end point for the Kondo volume collapse model,  Phys. Rev. Lett. 97, 185701 (2006).

  5. Jacob D. Stevenson, Joerg Schmalian, Peter G. Wolynes The Shapes of Cooperatively Rearranging Regions in Glass Forming Liquids,  Nature-Physics 4 268 (2006).

  6. Zaanen J, Chakravarty S, Senthil T, Anderson P, Lee P. A. , Schmalian J, Imada M, Pines D, Randeria M, Varma C, Vojta M, Rice T. M,  Towards a complete theory of high Tc , Nature Physics, 2 ,  138-143 (2006).

  7. M. I Mendelev, J. Schmalian, C. Z. Wang, J. R. Morris, K. M. Ho, Interface mobility and the liquid-Glass transition in a one component system described by an embedded atom method potential ,  Physical Review B 74, 104206 (2006).

  8. N. J. Curro, B. L.  Young, J.  Schmalian, D. Pines, Universal scaling behavior in heavy electron materials, Physica B 378-80 754 (2006).

  9. Thomas Vojta and Joerg Schmalian, Percolation quantum phase transition in diluted magnets, Phys. Rev. Lett. 95, 237206 (2005).

  10. C. Johnston, S.-H. Baek, X. Zong, F. Borsa, J. Schmalian, S. Kondo , Dynamics of Magnetic Defects in Heavy Fermion LiV2O4 from Stretched Exponential 7Li NMR Relaxation,  Phys. Rev. Lett. 95, 176408 (2005). 

  11. Andrey Chubukov and Joerg Schmalian, Strong coupling superconductivity due to massless boson exchange in the strong-coupling limit,  Phys. Rev. B 72, 174520 (2005).

  12. A. J. Millis, D. K. Morr and J. Schmalian, Comment on "Quantum Griffiths effects in metallic systems" by A. H. Castro Neto and B. A. Jones, Europhysics Letters 72, 1052 (2005).

  13. Maxim Dzero, Joerg Schmalian, and Peter G. Wolynes, Activated events in glasses: the structure of entropic droplets,  Phys. Rev. B, Rapid Comm. 72, 100201 (2005).

  14. Harry Westfahl, Jr. and Joerg Schmalian, Correlated disorder in random block copolymers, Phys. Rev. E 72, 011806 (2005).

  15. Thomas Vojta and Joerg Schmalian,  Quantum Griffiths effects in itinerant Heisenberg magnets, Phys. Rev. B 72, 045438 (2005) [also listed in: Virtual Journal of Nanoscale Science & Technology 12 issue 4 (2005)].

  16. Joerg Schmalian, Peter G. Wolynes, Electronic Mayonnaise: Uniting the Sciences of "Hard" and "Soft" Matter, Materials Research Society, Bulletin 30, 433 (2005)

  17. Jun Liu, Joerg Schmalian, Nandini Trivedi, Pairing and superconductivity driven by strong quasiparticle renormalization in two-dimensional organic charge transfer salts,   Phys. Rev. Lett 94, 127003 (2005).

  18.  Maxim Dzero, Joerg Schmalian, Superconductivity in charge Kondo systems, Phys. Rev. Lett. 94, 157003 (2005).

  19. Kok-Kiong Loh, Kyozi Kawasaki, Alan R. Bishop, Turab Lookman, Avadh Saxena, Joerg Schmalian, Zohar Nussinov, Glassy behavior in systems with Kac-type step-function interaction, Phys. Rev. E,  Rapid Comm. 69, 010501 (2004).

  20.  J. Schmalian and M. Turlakov , Quantum Phase Transitions of Magnetic Rotons, Phys. Rev. Lett. 93, 036405 (2004).

  21. S. Wu, J. Schmalian, G. Kotliar, and P. G. Wolynes, Solution of local-field equations for self-generated glasses, Phys. Rev. B 70, 024207 (2004).

  22. N. J. Curro, B.-L. Young, J. Schmalian, D. Pines,  Scaling in the Emergent Behavior of Heavy Electron Materials,  Phys. Rev. B 70, 235117 (2004).

  23. H. Westfahl Jr., J. Schmalian, P. G. Wolynes, Dynamical mean-field theory of quantum stripe glasses, Phys. Rev. B 68, 134203 (2003).

  24. M. Hupalo, J. Schmalian, M. C. Tringides,  Devil's staircase  in Pb/Si(111) Ordered Phases, Physical Review Letters  (2003), 90, 216106

  25. A. V. Chubukov, D. Pines, J. Schmalian, A spin fluctuation model for d-wave superconductivity. Physics of Superconductors (2003), 1 495

  26. Ar. Abanov, A. V. Chubukov,  J. Schmalian, Quantum-critical theory of the spin-fermion model and its application to cuprates:  normal state analysis.  Advances in Physics (2003), 52(3), 119

  27. Ar. Abanov, A. V. Chubukov, M. Eschrig, M. R. Norman, J. Schmalian, Neutron Resonance in the Cuprates and its Effect on Fermionic Excitations.  Physical Review Letters (2002), 89(17), 17700

  28.  A. J. Millis, D. K, Morr, J. Schmalian, Quantum Griffiths effects in metallic systems.  Physical Review B: Condensed Matter and Materials Physics (2002), 66(17), 174433

  29. S. Wu, H. Westfahl Jr., J. Schmalian, and P. G. Wolynes,  Theory of Microemulsion Glasses,  Chem. Phys. Lett. 359, 1-7 (2002).

  30. A. J. Millis, D. K. Morr, J. Schmalian, Local Defect in Metallic Quantum Critical Systems, Phys. Rev. Lett. 87 167202 (2001).

  31. H. Westfahl Jr., J. Schmalian, P. G. Wolynes, Self generated randomness, defect wandering and viscous flow in stripe glasses, Phys. Rev. B 64, 174203 (2001).

  32. Ar. Abanov, A. Chubukov, and J. Schmalian:  Quantum critical pairing in cuprates, Europhys. Lett. 55, 369-375  (2001).

  33. Ar. Abanov, A. Chubukov, and J. Schmalian:   Singularities in the optical response of cuprates, Phys. Rev. B 63, 180510/1 (2001).

  34. Ar. Abanov, A. Chubukov and J. Schmalian:   Fingerprints for spin-mediated pairing in cuprates, Journal of Electron Spectroscopy and Related Phenomena 117, 129-151 (2001).

  35. J. Schmalian and Peter G. Wolynes, Schmalian and Wolynes Reply,Phys. Rev. Lett. 86, 3456 (2001).

  36. J. Schmalian, P. G. Wolynes:  Stripe Glasses: Self-Generated Randomness in a Uniformly Frustrated System. Phys. Rev. Lett. (2000), 85, 836-839.

  37. J. Schmalian, H. Westfahl Jr., and Peter G. Wolynes: On the number of metastable states in stripe glasses. Intl. Journal of Modern Physics B 15, 3292 (2001)

  38. S. Langridge, J. Schmalian, C. H. Marrows, D. T. Dekadjevi, and B. J. Hickey: Quantification of magnetic domain disorder and correlations in antiferromagnetically coupled multilayers by neutron reflectometry, Phys. Rev. Lett. 85, 4964 (2000).

  39. D. E. Sheehy, P. M. Goldbart, J. Schmalian, A. Yazdani Andreev interferometry as a probe of superconducting phase correlations in the pseudogap regime of the cuprates, Phys Rev. B 62, 4105  (2000).

  40. S. Langridge, J. Schmalian, C. H. Marrows, D. T. Dekadjevi, A neutron study of magnetic domain correlations in antiferromagnetically coupled multilayers, Journal of Applied Physics, 87, 5750 (2000).

  41. R. B. Laughlin, D. Pines, J. Schmalian, B. P. Stojkovic, and P. G. Wolynes, The Middle Way.  Proc. of the Nat. Acad. of Sciences, 97, 32 (2000).

  42. T. Nunner, J. Schmalian, and K. H. Bennemann, Influence of Electron-Phonon Interaction on Spin Fluctuation Induced Superconductivity,  Phys. Rev. B 59, 8859 (1999).

  43. J. Schmalian, D. Pines, and B. P. Stojkovic, Microscopic theory of weak pseudogap behavior in the underdoped cuprate superconductors: General theory and quasiparticle properties Phys. Rev. B 60, 667 (1999).

  44. G. Hildebrand, E. Arrigoni, J. Schmalian, and W. Hanke, Magnetic coupling in inequivalent Hubbard layers as a model for Y2Ba4Cu7O15, European Physical Journal 8, 195 (1999).

  45. J. Schmalian and K. H. Bennemann, Analysis of Properties of High-Tc Superconductors Studies in High. Temperature Superconductors 27 (Pseudogap in High temperature superconductors), p. 1 (1999).

  46. G. Hildebrand, E. Arrigoni, J. Schmalian, and W. Hanke,Interplane magnetic coupling effects in the multilattice compound Y2Ba4Cu7O15, Phys. Rev. B (Rapid Communication), 59 R685, (1999).

  47. J. Schmalian, Pairing due to Spin Fluctuations in Layered Organic Superconductors, Phys. Rev. Lett. 81, 4232 (1998).

  48. J. Schmalian, D. Pines, and B. Stojkovic, Weak pseudogap behavior in the underdoped cuprate superconductors Phys. Rev. Lett. 80, 3839 (1998).

  49. D. K. Morr, J. Schmalian, R. Stern, C. P. Slichter, Probing the susceptibility in cuprates using Ni impurities, Phys. Rev. B 58, 11193 (1998); Erratum: Phys. Rev. B 59, 8984 (1999).

  50. J. Schmalian and D. Pines, Materials driven Science: from high-Tc to complex adaptive matter, Proceedings of the NATO Advanced Study Institute conference on Soft Condensed Matter: Configurations, Dynamics and Functionality, April 6-16, 1999, Geilo, Norway

  51. F. Schaefer, J. Schmalian, and K. H. Bennemann, Superconductivity in the Three Band Hubbard Model, Phys. Rev. B 58, 15177 (1998).

  52. J. Schmalian, D. Pines, and B. Stojkovic, Weak pseudogap behavior un the underdoped cuprate superconductors  Proceedings of the Conference on spectroscopy in novel superconductors-SNS'97 in Cape Cod, Massachusetts. Journal of Physics and Chemistry of Solids 59, 1764 (1998).

  53. A. Chubukov and J. Schmalian, Temperature variation of the pseudogap in underdoped cuprates Phys. Rev. B 57, R11085 (1998).

  54. S. Grabowski, J. Schmalian, K. H. Bennemann, and J. L. Moran-Lopez, Spin Fluctuation Effects in High-Tc Superconductors Current Problems in Condensed Matter, 5-9 Jan. 1997, Cocoyoc, Mexico; Plenum Press, New York (1998) p. 1-9.

  55. P. Lombardo, J. Schmalian, M. Avignon, K.H. Bennemann, J. L. Moran-Lopez, Spectral properties of transition metal compounds and metal-insulator transition: A systematic approach within the dynamical mean field theory,  Current Problems in Condensed Matter, 5-9 Jan. 1997, Cocoyoc, Mexico; Plenum Press, New York (1998) p. 95-108.

  56. D. K.  Morr, J. Schmalian, R. Stern, and C. P. Slichter, Comment on:  Using Ni Substitution and O-NMR to Probe the Susceptibility \chi^\prime(q) in Cuprates,  by Bobroff et al. PRL 79, 2117 (1997); Phys. Rev. Lett. 80, 3662 (1998).

  57. P. Slichter, R. Corey, N. Curro, J. Haase, C. Milling, D. Morr, J. Schmalian, R. Stern,  J-Coupling in High Temperature Superconductors,  Molecular-Physics 95, 897 (1998).

  58. G. Hildebrand, T. J. Haagenaars, W. Hanke, S. Grabowski, and J. Schmalian,  Effects of electronic correlations on the thermoelectric power of the cuprates, Phys. Rev. B 56, R4317, (1997).

  59. S. Grabowski, J. Schmalian and K .H. Bennemann,  Doping Dependence of the Superconducting State of the cuprates,  Proceedings of the International Conference on Superconducting Mechanisms and Materials, Bejing 1997, Physica C 282-287, 1775 (1997)

  60. J. Schmalian, S. Grabowski and K. H. Bennemann,  Doping Dependence of the Superconducting State in High-Tc Systems,  Proceedings of the Euroconference, Correlations in Unconventional Quantum Liquids, Evora, Portugal, October 7 to 11, 1996,  Zeitschrift f. Physik B 103, 145 (1997).

  61. J. Schmalian, S. Grabowski, and K .H. Bennemann,  Analysis of Characteristic Temperatures in High-Tc systems,  Phys. Rev. B 56, R509, (1997).

  62. S. Grabowski, M. Langer , J. Schmalian, and K. H. Bennemann,   Electronic theory for bilayer effects in High-Tc superconductors,  Phys. Rev. B 55, 2784, (1997).

  63. S. Grabowski, M. Langer,  J. Schmalian, and K. H. Bennemann,  High-Tc-Superconductivity and Shadow State Formation in YBa2Cu3O6+y and Bi2Sr2CaCu2O8+xSolid State Communications 102, 493 (1997).

  64. S. Grabowski, J. Schmalian and K. H. Bennemann,   Electronic Theory for bilayer effects in high temperature superconductors,  Proceedings of the International Conference on Superconducting Mechanisms and Materials, Bejing 1997, Physica C 282-287, 1681 (1997).

  65. P. Lombardo, J. Schmalian, M. Avignon, K. H. Bennemann, Coherent quasi particle evolution in charge transfer systems: a dynamical mean field theory,  Proceedings of the International Conference on Strongly Correlated Electron Systems, SCES '96, Zurich, Switzerland, 19-22 Aug. 1996, Physica B 230-232, 415 (1997).

  66. S. Grabowski, J. Schmalian and K. H. Bennemann,  Electronic Theory For Bilayer Effects in High-Tc Superconductors,  Proceedings of the International Conference on Strongly Correlated Electron Systems, SCES '95, Zurich, Switzerland, 19-22 Aug. 1996, Physica B 230-232, 948 (1997).

  67. J. Schmalian, S. Grabowski, and K. H. Bennemann,  Superconductivity and Dynamical Short Range Order in High-Tc Systems,  Proceedings of the International Conference on Strongly Correlated Electron Systems, SCES '95, Zurich, Switzerland, 19-22 Aug. 1996, Physica B 230-232, 922 (1997).

  68. J. Schmalian, M. Langer, S. Grabowski, K. H. Bennemann, Theory for Dynamical Short Range Order and Fermi Surface Volume in Strongly Correlated Systems, Phys. Rev. B 54, 4336 (1996).

  69. P. Lombardo, J. Schmalian, M. Avignon, K. H. Bennemann,  Dynamical Mean Field Theory for Perovskites:  Phys. Rev. B 54, 5317 (1996).

  70. S. Grabowski, M. Langer, J. Schmalian, K. H. Bennemann,  Theory for superconducting properties of the cuprates: Doping dependence of the electronic excitations and shadow states,  Europhys. Lett. 34 219 (1996).

  71. S. Grabowski, J. Schmalian, M. Langer, and K. H. Bennemann,  Theory for the Interdependence of High-Tc Superconductivity and Dynamical Spin Fluctuations,  Solid State Commun. 98, 611 (1996).

  72. J. Schmalian und W. Huebner,  Nonlinear magneto-optical response of s- and d-wave Superconductors,  Phys. Rev. B 53, 11860 (1996).

  73. M. Langer, J. Schmalian, S. Grabowski, K. H. Bennemann,  Theory for the doping dependence of spin fluctuation induced shadow states in high-Tc-superconductors,  Physics Letters A 212, 270 (1996).

  74. J. Schmalian, M. Langer, S. Grabowski, and K. H. Bennemann,  Self Consistent Summation of Many-Particle Diagrams on the Real Frequency Axis and its Application to the FLEX approximation,  Computer Physics Communications 93, 141 (1996).

  75. M. Langer, J. Schmalian, S. Grabowski, and K. H. Bennemann,  Electronic Theory for the Transition from Fermi-Liquid to non-Fermi-Liquid Behavior in High-Tc Superconductors,  Solid State Communications 97, 663 (1996).

  76. J. Schmalian, P. Lombardo, M. Avignon, K.H. Bennemann,  A new approach for perorskites in large dimensions, Proceedings of the International Conference on Strongly Correlated Electron Systems, SCES '95, Goa.  India, 27-30 Sept. 1995, Physica B 223, 602 (1996).

  77. M. Langer, J. Schmalian, S. Grabowski, K. H. Bennemann, Theory for the Excitation Spectrum of High-Tc Superconductors: Quasiparticle Dispersion and Shadows of the Fermi Surface,  Phys. Rev. Lett. 75, 4508 (1995).

  78. G. Baumgaertel, J. Schmalian, and K. H. Bennemann, Theory for normal state magnetic properties of High-Tc superconductors: doping and temperature dependence,  Recent Progress in Many Body Theory 4, 393 (1995).

  79. C. Lehner, G. Baumgaertel, J. Schmalian, and K. H. Benneman,  Theory for the Transfer of Spectral Weight in the Electronic Spectral Density of Strongly Correlated Systems  Solid State Comm. 89, 719 (1994).

  80. G. Baumgaertel, J. Schmalian, and K. H. Bennemann, Theory for the Static Spin Susceptibility of High-Tc Superconductors: Temperature and Doping Dependence Europhys. Lett 24, 601 (1993).

  81. G. Baumgaertel, J. Schmalian, and K. H. Bennemann,  Theory for the Electronic Structure of High-Tc Superconductors  Phys. Rev. B 48, 3983 (1993).

  82. J. Schmalian, G. Baumgaertel, and K. H. Bennemann,  Doping Dependence of Local Magnetic Moments and Antiferromagnetism in High--Tc Superconductors: Asymmetry Between Electron and Hole Doping   Solid State Comm.  86, 119 (1993).

  83. J. Schmalian, G. Baumgaertel, and K. H. Bennemann, Elementary Excitations in the Metallic CuO2 Planes of High-Tc Systems   Phys. Rev. Lett.  68, 1406 (1992).

     

     


     UPDATED: 4 November 2007

 


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