Bio


I am interested in the emergent behavior of quantum condensed matter systems. Some recent research topics include non-Fermi liquids, quantum criticality, statistical mechanics of strongly interacting and disordered quantum systems, physics of the half-filled Landau level, quantum Hall to insulator transitions, superconductor-metal-insulator transitions, and the phenomenology of quantum materials.

Past contributions that I'm particularly proud of include the co-founding of the subject of topological photonics (with Duncan Haldane), scaling theories of non-Fermi liquid metals (with Shamit Kachru and Gonzalo Torroba), Euclidean lattice descriptions of Chern-Simons matter theories and their dualities in 2+1 dimensions (with Jing-Yuan Chen and Jun Ho Son), and 'dual' perspectives of quantum Hall transitions (with Prashant Kumar and Michael Mulligan).

Academic Appointments


Administrative Appointments


  • Postdoctoral Scholar, Stanford University (2006 - 2010)
  • Assistant Professor, Rice University (2010 - 2011)
  • Assistant Professor, Department of Physics, Stanford University (2011 - 2017)
  • Associate Professor, Department of Physics, Stanford (2017 - Present)

Honors & Awards


  • Elected Fellow, American Physical Society
  • Terman Fellowship, Stanford University (2012)
  • Sloan Research Fellowship, Alfred P. Sloan Foundation (2012)
  • Young Investigator Award, U.S. Departrment of Energy (2012)

Professional Education


  • Ph.D., Princeton University, Physics (2006)

2023-24 Courses


Stanford Advisees


All Publications


  • Linear-in-temperature resistivity for optimally superconducting (Nd,Sr)NiO2. Nature Lee, K., Wang, B. Y., Osada, M., Goodge, B. H., Wang, T. C., Lee, Y., Harvey, S., Kim, W. J., Yu, Y., Murthy, C., Raghu, S., Kourkoutis, L. F., Hwang, H. Y. 2023; 619 (7969): 288-292

    Abstract

    The occurrence of superconductivity in proximity to various strongly correlated phases of matter has drawn extensive focus on their normal state properties, to develop an understanding of the state from which superconductivity emerges1-4. The recent finding of superconductivity in layered nickelates raises similar interests5-8. However, transport measurements of doped infinite-layer nickelate thin films have been hampered by materials limitations of these metastable compounds: in particular, a high density of extended defects9-11. Here, by moving to a substrate (LaAlO3)0.3(Sr2TaAlO6)0.7 that better stabilizes the growth and reduction conditions, we can synthesize the doping series of Nd1-xSrxNiO2 essentially free from extended defects. In their absence, the normal state resistivity shows a low-temperature upturn in the underdoped regime, linear behaviour near optimal doping and quadratic temperature dependence for overdoping. This is phenomenologically similar to the copper oxides2,12 despite key distinctions-namely, the absence of an insulating parent compound5,6,9,10, multiband electronic structure13,14 and a Mott-Hubbard orbital alignment rather than the charge-transfer insulator of the copper oxides15,16. We further observe an enhancement of superconductivity, both in terms of transition temperature and range of doping. These results indicate a convergence in the electronic properties of both superconducting families as the scale of disorder in the nickelates is reduced.

    View details for DOI 10.1038/s41586-023-06129-x

    View details for PubMedID 37438595

    View details for PubMedCentralID 7812792

  • The Hubbard Model ANNUAL REVIEW OF CONDENSED MATTER PHYSICS Arovas, D. P., Berg, E., Kivelson, S. A., Raghu, S. 2022; 13: 239-274
  • Universal behavior of the bosonic metallic ground state in a two-dimensional superconductor NPJ QUANTUM MATERIALS Chen, Z., Wang, B., Swartz, A. G., Yoon, H., Hikita, Y., Raghu, S., Hwang, H. Y. 2021; 6 (1)
  • Robust dx2-y2-wave superconductivity of infinite-layer nickelates PHYSICAL REVIEW B Wu, X., Di Sante, D., Schwemmer, T., Hanke, W., Hwang, H. Y., Raghu, S., Thomale, R. 2020; 101 (6)
  • Two-Dimensional Non-Fermi-Liquid Metals: A Solvable Large-N Limit. Physical review letters Damia, J. A., Kachru, S., Raghu, S., Torroba, G. 2019; 123 (9): 096402

    Abstract

    Significant effort has been devoted to the study of "non-Fermi-liquid" (NFL) metals: gapless conducting systems that lack a quasiparticle description. One class of NFL metals involves a finite density of fermions interacting with soft order parameter fluctuations near a quantum critical point. The problem has been extensively studied in a large-N limit (N corresponding to the number of fermion flavors) where universal behavior can be obtained by solving a set of coupled saddle-point equations. However, a remarkable study by Lee revealed the breakdown of such approximations in two spatial dimensions. We show that an alternate approach, in which the fermions belong to the fundamental representation of a global SU(N) flavor symmetry, while the order parameter fields transform under the adjoint representation (a "matrix large-N" theory), yields a tractable large N limit. At low energies, the system consists of an overdamped boson with dynamical exponent z=3 coupled to a non-Fermi-liquid with self-energy Σ(ω)∼ω^{2/3}, consistent with previous studies.

    View details for DOI 10.1103/PhysRevLett.123.096402

    View details for PubMedID 31524468

  • Two-Dimensional Non-Fermi-Liquid Metals: A Solvable Large-N Limit PHYSICAL REVIEW LETTERS Aguilera Damia, J., Kachru, S., Raghu, S., Torroba, G. 2019; 123 (9)
  • Publisher Correction: Carrier density and disorder tuned superconductor-metal transition in a two-dimensional electron system. Nature communications Chen, Z., Swartz, A. G., Yoon, H., Inoue, H., Merz, T. A., Lu, D., Xie, Y., Yuan, H., Hikita, Y., Raghu, S., Hwang, H. Y. 2018; 9 (1): 4570

    Abstract

    The original HTML version of this Article omitted to list Harold Y. Hwang as a corresponding author and incorrectly listed Adrian G. Swartz as a corresponding author. This has been corrected in the HTML version of the Article. The PDF version was correct from the time of publication.

    View details for PubMedID 30374115

  • Superconducting Tunneling Spectroscopy of Spin-Orbit Coupling and Orbital Depairing in Nb :SrTiO3 PHYSICAL REVIEW LETTERS Swartz, A. G., Cheung, A. C., Yoon, H., Chen, Z., Hikita, Y., Raghu, S., Hwang, H. Y. 2018; 121 (16): 167003

    Abstract

    We have examined the intrinsic spin-orbit coupling and orbital depairing in thin films of Nb-doped SrTiO_{3} by superconducting tunneling spectroscopy. The orbital depairing is geometrically suppressed in the two-dimensional limit, enabling a quantitative evaluation of the Fermi level spin-orbit scattering using Maki's theory. The response of the superconducting gap under in-plane magnetic fields demonstrates short spin-orbit scattering times τ_{so}≤1.1  ps. Analysis of the orbital depairing indicates that the heavy electron band contributes significantly to pairing. These results suggest that the intrinsic spin-orbit scattering time in SrTiO_{3} is comparable to those associated with Rashba effects in SrTiO_{3} interfacial conducting layers and can be considered significant in all forms of superconductivity in SrTiO_{3}.

    View details for PubMedID 30387624

  • Carrier density and disorder tuned superconductor-metal transition in a two-dimensional electron system NATURE COMMUNICATIONS Chen, Z., Swartz, A. G., Yoon, H., Inoue, H., Merz, T. A., Lu, D., Xie, Y., Yuan, H., Hikita, Y., Raghu, S., Hwang, H. Y. 2018; 9
  • Carrier density and disorder tuned superconductor-metal transition in a two-dimensional electron system. Nature communications Chen, Z., Swartz, A. G., Yoon, H., Inoue, H., Merz, T. A., Lu, D., Xie, Y., Yuan, H., Hikita, Y., Raghu, S., Hwang, H. Y. 2018; 9 (1): 4008

    Abstract

    Quantum ground states that arise at atomically controlled oxide interfaces provide an opportunity to address key questions in condensed matter physics, including the nature of two-dimensional metallic behaviour often observed adjacent to superconductivity. At the superconducting LaAlO3/SrTiO3 interface, a metallic ground state emerges upon the collapse of superconductivity with field-effect gating and is accompanied with a pseudogap. Here we utilize independent control of carrier density and disorder of the interfacial superconductor using dual electrostatic gates, which enables the comprehensive examination of the electronic phase diagram approaching zero temperature. We find that the pseudogap corresponds to precursor pairing, and the onset of long-range phase coherence forms a two-dimensional superconducting dome as a function of the dual-gate voltages. The gate-tuned superconductor-metal transitions are driven by macroscopic phase fluctuations of Josephson coupled superconducting puddles.

    View details for PubMedID 30275443

  • Polaronic behavior in a weak-coupling superconductor PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Swartz, A. G., Inoue, H., Merz, T. A., Hikita, Y., Raghu, S., Devereaux, T. P., Johnston, S., Hwang, H. Y. 2018; 115 (7): 1475–80

    Abstract

    The nature of superconductivity in the dilute semiconductor SrTiO3 has remained an open question for more than 50 y. The extremely low carrier densities ([Formula: see text]-[Formula: see text] cm-3) at which superconductivity occurs suggest an unconventional origin of superconductivity outside of the adiabatic limit on which the Bardeen-Cooper-Schrieffer (BCS) and Migdal-Eliashberg (ME) theories are based. We take advantage of a newly developed method for engineering band alignments at oxide interfaces and access the electronic structure of Nb-doped SrTiO3, using high-resolution tunneling spectroscopy. We observe strong coupling to the highest-energy longitudinal optic (LO) phonon branch and estimate the doping evolution of the dimensionless electron-phonon interaction strength ([Formula: see text]). Upon cooling below the superconducting transition temperature ([Formula: see text]), we observe a single superconducting gap corresponding to the weak-coupling limit of BCS theory, indicating an order of magnitude smaller coupling ([Formula: see text]). These results suggest that despite the strong normal state interaction with electrons, the highest LO phonon does not provide a dominant contribution to pairing. They further demonstrate that SrTiO3 is an ideal system to probe superconductivity over a wide range of carrier density, adiabatic parameter, and electron-phonon coupling strength.

    View details for PubMedID 29382769

  • Non-Fermi-liquid superconductivity: Eliashberg approach versus the renormalization group PHYSICAL REVIEW B Wang, H., Raghu, S., Torroba, G. 2017; 95 (16)
  • Emergent particle-hole symmetry in the half-filled Landau level PHYSICAL REVIEW B Mulligan, M., Raghu, S., Fisher, M. P. 2016; 94 (7)
  • Spin-orbit coupling and odd-parity superconductivity in the quasi-one-dimensional compound Li0.9Mo6O17 PHYSICAL REVIEW B Platt, C., Cho, W., McKenzie, R. H., Thomale, R., Raghu, S. 2016; 93 (21)
  • Composite fermions and the field-tuned superconductor-insulator transition PHYSICAL REVIEW B Mulligan, M., Raghu, S. 2016; 93 (20)
  • Topological properties of ferromagnetic superconductors PHYSICAL REVIEW B Cheung, A. K., Raghu, S. 2016; 93 (13)
  • Metallic quantum critical points with finite BCS couplings PHYSICAL REVIEW B Raghu, S., Torroba, G., Wang, H. 2015; 92 (20)
  • Spin-triplet superconductivity in a weak-coupling Hubbard model for the quasi-one-dimensional compound Li0.9Mo6O17 PHYSICAL REVIEW B Cho, W., Platt, C., McKenzie, R. H., Raghu, S. 2015; 92 (13)
  • Elastoconductivity as a probe of broken mirror symmetries PHYSICAL REVIEW B Hlobil, P., Maharaj, A. V., Hosur, P., SHAPIRO, M. C., Fisher, I. R., Raghu, S. 2015; 92 (3)
  • Enhanced pairing of quantum critical metals near d=3+1 PHYSICAL REVIEW B Fitzpatrick, A. L., Kachru, S., Kaplan, J., Raghu, S., Torroba, G., Wang, H. 2015; 92 (4)
  • Evidence for a nematic component to the hidden-order parameter in URu2Si2 from differential elastoresistance measurements NATURE COMMUNICATIONS Riggs, S. C., SHAPIRO, M. C., Maharaj, A. V., Raghu, S., Bauer, E. D., Baumbach, R. E., Giraldo-Gallo, P., Wartenbe, M., Fisher, I. R. 2015; 6

    View details for DOI 10.1038/ncomms7425

    View details for Web of Science ID 000352633900009

    View details for PubMedID 25742938

  • Evidence for a nematic component to the hidden-order parameter in URu2Si2 from differential elastoresistance measurements. Nature communications Riggs, S. C., SHAPIRO, M. C., Maharaj, A. V., Raghu, S., Bauer, E. D., Baumbach, R. E., Giraldo-Gallo, P., Wartenbe, M., Fisher, I. R. 2015; 6: 6425-?

    Abstract

    For materials that harbour a continuous phase transition, the susceptibility of the material to various fields can be used to understand the nature of the fluctuating order and hence the nature of the ordered state. Here we use anisotropic biaxial strain to probe the nematic susceptibility of URu2Si2, a heavy fermion material for which the nature of the low temperature 'hidden order' state has defied comprehensive understanding for over 30 years. Our measurements reveal that the fluctuating order has a nematic component, confirming reports of twofold anisotropy in the broken symmetry state and strongly constraining theoretical models of the hidden-order phase.

    View details for DOI 10.1038/ncomms7425

    View details for PubMedID 25742938

  • Suppression of spontaneous currents in Sr2RuO4 by surface disorder PHYSICAL REVIEW B Lederer, S., Huang, W., Taylor, E., Raghu, S., Kallin, C. 2014; 90 (13)
  • Crisscrossed stripe order from interlayer tunneling in hole-doped cuprates PHYSICAL REVIEW B Maharaj, A. V., Hosur, P., Raghu, S. 2014; 90 (12)
  • Anomalous Fermi-liquid phase in metallic skyrmion crystals PHYSICAL REVIEW B Watanabe, H., Parameswaran, S. A., Raghu, S., Vishwanath, A. 2014; 90 (4)
  • Non-Fermi-liquid behavior of large-N-B quantum critical metals PHYSICAL REVIEW B Fitzpatrick, A. L., Kachru, S., Kaplan, J., Raghu, S. 2014; 89 (16)
  • Tunable coupling of two-dimensional superconductors in bilayer SrTiO3 heterostructures PHYSICAL REVIEW B Inoue, H., Kim, M., Bell, C., Hikita, Y., Raghu, S., Hwang, H. Y. 2013; 88 (24)
  • Particle-hole condensates of higher angular momentum in hexagonal systems PHYSICAL REVIEW B Maharaj, A. V., Thomale, R., Raghu, S. 2013; 88 (20)
  • Non-Fermi-liquid fixed point in a Wilsonian theory of quantum critical metals PHYSICAL REVIEW B Fitzpatrick, A. L., Kachru, S., Kaplan, J., Raghu, S. 2013; 88 (12)
  • Quantum critical metals in d=3+1 dimensions PHYSICAL REVIEW B Mahajan, R., Ramirez, D. M., Kachru, S., Raghu, S. 2013; 88 (11)
  • Band structure effects on the superconductivity in Hubbard models PHYSICAL REVIEW B Cho, W., Thomale, R., Raghu, S., Kivelson, S. A. 2013; 88 (6)
  • Higher angular momentum pairing from transverse gauge interactions PHYSICAL REVIEW B Chung, S. B., Mandal, I., Raghu, S., Chakravarty, S. 2013; 88 (4)
  • Kerr effect as evidence of gyrotropic order in the cuprates PHYSICAL REVIEW B Hosur, P., Kapitulnik, A., Kivelson, S. A., Orenstein, J., Raghu, S. 2013; 87 (11)
  • Spin-orbit coupling in LaAlO3/SrTiO3 interfaces: magnetism and orbital ordering NEW JOURNAL OF PHYSICS Fischer, M. H., Raghu, S., Kim, E. 2013; 15
  • Theory of 'hidden' quasi-1D superconductivity in Sr2RuO4 10th International Conference on Materials and Mechanisms of Superconductivity (M2S) Raghu, S., Chung, S. B., Lederer, S. IOP PUBLISHING LTD. 2013
  • Optimal T-c of cuprates: The role of screening and reservoir layers PHYSICAL REVIEW B Raghu, S., Thomale, R., Geballe, T. H. 2012; 86 (9)
  • Charge and spin collective modes in a quasi-one-dimensional model of Sr2RuO4 PHYSICAL REVIEW B Chung, S. B., Raghu, S., Kapitulnik, A., Kivelson, S. A. 2012; 86 (6)
  • Field-Induced p-Wave Superconducting State of Mesoscopic Systems PHYSICAL REVIEW LETTERS Huo, J., Chen, W., Raghu, S., Zhang, F. 2012; 108 (25)

    Abstract

    By using Bogoliubov-de Gennes equations, we study superconducting (SC) states in a quasi-two-dimensional system of radius R. It is shown that no vortices exist in s-wave SC samples with R < R(c) ~ ξ(0), the T = 0 coherence length. We predict that chiral p-wave states exhibit superconductivity for R < R(c) only in the presence of a vortex with opposite chirality. This induced SC phase is a consequence of nonzero chirality of the pairing order parameter and implies the presence of chiral edge currents. Our study may be applied to sharply probing the pairing symmetry of unconventional superconductors.

    View details for DOI 10.1103/PhysRevLett.108.257002

    View details for Web of Science ID 000305541000015

    View details for PubMedID 23004642

  • Majorana zero modes in a quantum Ising chain with longer-ranged interactions PHYSICAL REVIEW B Niu, Y., Chung, S. B., Hsu, C., Mandal, I., Raghu, S., Chakravarty, S. 2012; 85 (3)
  • Effects of longer-range interactions on unconventional superconductivity PHYSICAL REVIEW B Raghu, S., Berg, E., Chubukov, A. V., Kivelson, S. A. 2012; 85 (2)
  • Thermodynamics of phase formation in the quantum critical metal Sr3Ru2O7 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Rost, A. W., Grigera, S. A., Bruin, J. A., Perry, R. S., Tian, D., Raghu, S., Kivelson, S. A., Mackenzie, A. P. 2011; 108 (40): 16549-16553

    Abstract

    The behavior of matter near zero temperature continuous phase transitions, or "quantum critical points" is a central topic of study in condensed matter physics. In fermionic systems, fundamental questions remain unanswered: the nature of the quantum critical regime is unclear because of the apparent breakdown of the concept of the quasiparticle, a cornerstone of existing theories of strongly interacting metals. Even less is known experimentally about the formation of ordered phases from such a quantum critical "soup." Here, we report a study of the specific heat across the phase diagram of the model system Sr(3)Ru(2)O(7), which features an anomalous phase whose transport properties are consistent with those of an electronic nematic. We show that this phase, which exists at low temperatures in a narrow range of magnetic fields, forms directly from a quantum critical state, and contains more entropy than mean-field calculations predict. Our results suggest that this extra entropy is due to remnant degrees of freedom from the highly entropic state above T(c). The associated quantum critical point, which is "concealed" by the nematic phase, separates two Fermi liquids, neither of which has an identifiable spontaneously broken symmetry, but which likely differ in the topology of their Fermi surfaces.

    View details for DOI 10.1073/pnas.1112775108

    View details for Web of Science ID 000295536000020

    View details for PubMedID 21933961

    View details for PubMedCentralID PMC3189037

  • Superconductivity from repulsive interactions in the two-dimensional electron gas PHYSICAL REVIEW B Raghu, S., Kivelson, S. A. 2011; 83 (9)
  • Hidden Quasi-One-Dimensional Superconductivity in Sr2RuO4 PHYSICAL REVIEW LETTERS Raghu, S., Kapitulnik, A., Kivelson, S. A. 2010; 105 (13)

    Abstract

    We show that the interplay between spin and charge fluctuations in Sr₂RuO₄ leads unequivocally to triplet pairing which has a hidden quasi-one-dimensional character. The resulting superconducting state spontaneously breaks time-reversal symmetry and is of the form Δ ~(p(x)+ip(y))z(^) with sharp gap minima and a d vector that is only weakly pinned. The superconductor lacks robust chiral Majorana fermion modes along the boundary. The absence of topologically protected edge modes could explain the surprising absence of experimentally detectable edge currents in this system.

    View details for DOI 10.1103/PhysRevLett.105.136401

    View details for Web of Science ID 000282054100009

    View details for PubMedID 21230791

  • Superconductivity in the repulsive Hubbard model: An asymptotically exact weak-coupling solution PHYSICAL REVIEW B Raghu, S., Kivelson, S. A., Scalapino, D. J. 2010; 81 (22)
  • Collective Modes of a Helical Liquid PHYSICAL REVIEW LETTERS Raghu, S., Chung, S. B., Qi, X., Zhang, S. 2010; 104 (11)

    Abstract

    We study low energy collective modes and transport properties of the "helical metal" on the surface of a topological insulator. At low energies, electrical transport and spin dynamics at the surface are exactly related by an operator identity equating the electric current to the in-plane components of the spin degrees of freedom. From this relation it follows that an undamped spin wave always accompanies the sound mode in the helical metal-thus it is possible to "hear" the sound of spins. In the presence of long range Coulomb interactions, the surface plasmon mode is also coupled to the spin wave, giving rise to a hybridized "spin-plasmon" mode. We make quantitative predictions for the spin-plasmon in Bi2Se3, and discuss its detection in a spin-grating experiment.

    View details for DOI 10.1103/PhysRevLett.104.116401

    View details for Web of Science ID 000275802600032

    View details for PubMedID 20366490

  • Microscopic theory of the nematic phase in Sr3Ru2O7 PHYSICAL REVIEW B Raghu, S., Paramekanti, A., Kim, E. A., Borzi, R. A., Grigera, S. A., Mackenzie, A. P., Kivelson, S. A. 2009; 79 (21)
  • Time-Reversal-Invariant Topological Superconductors and Superfluids in Two and Three Dimensions PHYSICAL REVIEW LETTERS Qi, X., Hughes, T. L., Raghu, S., Zhang, S. 2009; 102 (18)

    Abstract

    We construct time-reversal invariant topological superconductors and superfluids in two and three dimensions. These states have a full pairing gap in the bulk, gapless counterpropagating Majorana states at the boundary, and a pair of Majorana zero modes associated with each vortex. The superfluid 3He B phase provides a physical realization of the topological superfluidity, with experimentally measurable surface states protected by the time-reversal symmetry. We show that the time-reversal symmetry naturally emerges as a supersymmetry, which changes the parity of the fermion number associated with each time-reversal invariant vortex and connects each vortex with its superpartner.

    View details for DOI 10.1103/PhysRevLett.102.187001

    View details for Web of Science ID 000265948600056

    View details for PubMedID 19518900

  • Vortex-dynamics approach to the Nernst effect in extreme type-II superconductors dominated by phase fluctuations PHYSICAL REVIEW B Raghu, S., Podolsky, D., Vishwanath, A., Huse, D. A. 2008; 78 (18)
  • Analogs of quantum-Hall-effect edge states in photonic crystals PHYSICAL REVIEW A Raghu, S., Haldane, F. D. 2008; 78 (3)
  • Minimal two-band model of the superconducting iron oxypnictides PHYSICAL REVIEW B Raghu, S., Qi, X., Liu, C., Scalapino, D. J., Zhang, S. 2008; 77 (22)
  • Topological Mott insulators PHYSICAL REVIEW LETTERS Raghu, S., Qi, X., Honerkamp, C., Zhang, S. 2008; 100 (15)

    Abstract

    We consider extended Hubbard models with repulsive interactions on a honeycomb lattice, and the transitions from the semimetal to Mott insulating phases at half-filling. Because of the frustrated nature of the second-neighbor interactions, topological Mott phases displaying the quantum Hall and the quantum spin Hall effects are found for spinless and spin fermion models, respectively. The mean-field phase diagram is presented and the fluctuations are treated within the random phase approximation. Renormalization group analysis shows that these states can be favored over the topologically trivial Mott insulating states.

    View details for DOI 10.1103/PhysRevLett.100.156401

    View details for Web of Science ID 000255117800048

    View details for PubMedID 18518132

  • Theory of the three-dimensional quantum hall effect in graphite PHYSICAL REVIEW LETTERS Bernevig, B. A., Hughes, T. L., Raghu, S., Arovas, D. P. 2007; 99 (14)

    Abstract

    We predict the existence of a three-dimensional quantum Hall effect plateau in a graphite crystal subject to a magnetic field. The plateau has a Hall conductivity quantized at 4e2/variant Planck's over 2pi 1/c0 with c0 the c-axis lattice constant. We analyze the three-dimensional Hofstadter problem of a realistic tight-binding Hamiltonian for graphite, find the gaps in the spectrum, and estimate the critical value of the magnetic field above which the Hall plateau appears. When the Fermi level is in the bulk Landau gap, Hall transport occurs through the appearance of chiral surface states. We estimate the magnetic field necessary for the appearance of the effect to be 15.4 T for electron carriers and 7.0 T for holes.

    View details for DOI 10.1103/PhysRevLett.99.146804

    View details for Web of Science ID 000249974000052

    View details for PubMedID 17930699

  • Nernst effect and diamagnetism in phase fluctuating superconductors PHYSICAL REVIEW LETTERS Podolsky, D., Raghu, S., Vishwanath, A. 2007; 99 (11)

    Abstract

    We study superconducting systems in the regime where superconductivity is destroyed by phase fluctuations. We find that the Nernst effect has a much sharper temperature decay than predicted by Gaussian fluctuations, with an onset temperature that tracks Tc rather than the pairing temperature. We find a close quantitative connection with diamagnetism--the ratio of magnetization to transverse thermoelectric conductivity reaches a fixed value at high temperatures. We interpret measurements on underdoped cuprates in terms of a dilute vortex liquid over a wide temperature range above Tc.

    View details for DOI 10.1103/PhysRevLett.99.117004

    View details for Web of Science ID 000249474700051

    View details for PubMedID 17930464