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Two-orbital S U(N) magnetism with ultracold alkaline-earth atoms

Abstract

Fermionic alkaline-earth atoms have unique properties that make them attractive candidates for the realization of atomic clocks and degenerate quantum gases. At the same time, they are attracting considerable theoretical attention in the context of quantum information processing. Here we demonstrate that when such atoms are loaded in optical lattices, they can be used as quantum simulators of unique many-body phenomena. In particular, we show that the decoupling of the nuclear spin from the electronic angular momentum can be used to implement many-body systems with an unprecedented degree of symmetry, characterized by the S U(N) group with N as large as 10. Moreover, the interplay of the nuclear spin with the electronic degree of freedom provided by a stable optically excited state should enable the study of physics governed by the spin–orbital interaction. Such systems may provide valuable insights into the physics of strongly correlated transition-metal oxides, heavy-fermion materials and spin-liquid phases.

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Figure 1: Interaction parameters between g and e atoms loaded in the lowest vibrational state of the corresponding optical lattice.
Figure 2: Young diagrams describing the irreducible representations of SU(N) on individual sites.
Figure 3: The ground-state phase diagram for the S U(N=2) Kugel–Khomskii model restricted to two wells, left and right.
Figure 4: Probing the phases of the SU(N) antiferromagnet on a 2D square lattice.
Figure 5: KLM for the case N=2.

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References

  1. Boyd, M. M. et al. Nuclear spin effects in optical lattice clocks. Phys. Rev. A 76, 022510 (2007).

    Article  ADS  Google Scholar 

  2. Campbell, G. K. et al. Probing interactions between ultracold fermions. Science 324, 360–363 (2009).

    Article  ADS  Google Scholar 

  3. Lemke, N. D. et al. Spin-1/2 optical lattice clock. Phys. Rev. Lett. 103, 063001 (2009).

    Article  ADS  Google Scholar 

  4. Fukuhara, T., Takasu, Y., Kumakura, M. & Takahashi, Y. Degenerate fermi gases of ytterbium. Phys. Rev. Lett. 98, 030401 (2007).

    Article  ADS  Google Scholar 

  5. Reichenbach, I. & Deutsch, I. H. Sideband cooling while preserving coherences in the nuclear spin state in group-II-like atoms. Phys. Rev. Lett. 99, 123001 (2007).

    Article  ADS  Google Scholar 

  6. Hayes, D., Julienne, P. S. & Deutsch, I. H. Quantum logic via the exchange blockade in ultracold collisions. Phys. Rev. Lett. 98, 070501 (2007).

    Article  ADS  Google Scholar 

  7. Daley, A. J., Boyd, M. M., Ye, J. & Zoller, P. Quantum computing with alkaline-earth-metal atoms. Phys. Rev. Lett. 101, 170504 (2008).

    Article  ADS  Google Scholar 

  8. Gorshkov, A. V. et al. Alkaline-earth-metal atoms as few-qubit quantum registers. Phys. Rev. Lett. 102, 110503 (2009).

    Article  ADS  Google Scholar 

  9. Kugel, K. I. & Khomskii, D. I. Crystal structure and magnetic properties of substances with orbital degeneracy. Sov. Phys. JETP 37, 725–730 (1973).

    ADS  Google Scholar 

  10. Arovas, D. P. & Auerbach, A. Tetrahis(dimethylamino)ethylene-C60: Multicomponent superexchange and Mott ferromagnetism. Phys. Rev. B 52, 10114–10121 (1995).

    Article  ADS  Google Scholar 

  11. Li, Y. Q., Ma, M., Shi, D. N. & Zhang, F. C. SU(4) theory for spin systems with orbital degeneracy. Phys. Rev. Lett. 81, 3527–3530 (1998).

    Article  ADS  Google Scholar 

  12. Pati, S. K., Singh, R. R. P. & Khomskii, D. I. Alternating spin and orbital dimerization and spin-gap formation in coupled spin–orbital systems. Phys. Rev. Lett. 81, 5406–5409 (1998).

    Article  ADS  Google Scholar 

  13. Tokura, Y. & Nagaosa, N. Orbital physics in transition-metal oxides. Science 288, 462–468 (2000).

    Article  ADS  Google Scholar 

  14. Ruderman, M. A. & Kittel, C. Indirect exchange coupling of nuclear magnetic moments by conduction electrons. Phys. Rev. 96, 99–102 (1954).

    Article  ADS  Google Scholar 

  15. Coqblin, B. & Schrieffer, J. R. Exchange interaction in alloys with cerium impurities. Phys. Rev. 185, 847–853 (1969).

    Article  ADS  Google Scholar 

  16. Doniach, S. The Kondo lattice and weak antiferromagnetism. Physica B+C 91, 231–234 (1977).

    Article  ADS  Google Scholar 

  17. Coleman, P. 1/N expansion for the Kondo lattice. Phys. Rev. B 28, 5255–5262 (1983).

    Article  ADS  Google Scholar 

  18. Tsunetsugu, H., Sigrist, M. & Ueda, K. The ground-state phase diagram of the one-dimensional Kondo lattice model. Rev. Mod. Phys. 69, 809–863 (1997).

    Article  ADS  Google Scholar 

  19. Assaad, F. F. Quantum Monte Carlo simulations of the half-filled two-dimensional Kondo lattice model. Phys. Rev. Lett. 83, 796–799 (1999).

    Article  ADS  Google Scholar 

  20. Tokura, Y. (ed.) Colossal Magnetoresistive Oxides (Gordon and Breach, 2000).

  21. Oshikawa, M. Topological approach to Luttinger’s theorem and the Fermi surface of a Kondo lattice. Phys. Rev. Lett. 84, 3370–3373 (2000).

    Article  ADS  Google Scholar 

  22. Senthil, T., Sachdev, S. & Vojta, M. Fractionalized Fermi liquids. Phys. Rev. Lett. 90, 216403 (2003).

    Article  ADS  Google Scholar 

  23. Duan, L.-M. Controlling ultracold atoms in multi-band optical lattices for simulation of Kondo physics. Europhys. Lett. 67, 721–727 (2004).

    Article  ADS  Google Scholar 

  24. Paredes, B., Tejedor, C. & Cirac, J. I. Fermionic atoms in optical superlattices. Phys. Rev. A. 71, 063608 (2005).

    Article  ADS  Google Scholar 

  25. Coleman, P. in Handbook of Magnetism and Advanced Magnetic Materials Vol. 1 (eds Kronmüller, H. & Parkin, S.) 95–148 (Wiley, 2007).

    Google Scholar 

  26. Gegenwart, P., Si, Q. & Steglich, F. Quantum criticality in heavy-fermion metals. Nature Phys. 4, 186–197 (2008).

    Article  ADS  Google Scholar 

  27. Read, N. & Sachdev, S. Valence-bond and spin-Peierls ground states of low-dimensional quantum antiferromagnets. Phys. Rev. Lett. 62, 1694–1967 (1989).

    Article  ADS  Google Scholar 

  28. Marston, J. B. & Affleck, I. Large-n limit of the Hubbard–Heisenberg model. Phys. Rev. B 39, 11538–11558 (1989).

    Article  ADS  MathSciNet  Google Scholar 

  29. Harada, K., Kawashima, N. & Troyer, M. Néel and spin-Peierls ground states of two-dimensional SU(N) quantum antiferromagnets. Phys. Rev. Lett. 90, 117203 (2003).

    Article  ADS  Google Scholar 

  30. Assaad, F. F. Phase diagram of the half-filled two-dimensional SU(N) Hubbard–Heisenberg model: A quantum Monte Carlo study. Phys. Rev. B 71, 075103 (2005).

    Article  ADS  Google Scholar 

  31. Paramekanti, A. & Marston, J. B. SU(N) quantum spin models: a variational wavefunction study. J. Phys. Condens. Matter 19, 125215 (2007).

    Article  ADS  Google Scholar 

  32. Greiter, M. & Rachel, S. Valence bond solids for SU(n) spin chains: Exact models, spinon confinement, and the Haldane gap. Phys. Rev. B 75, 184441 (2007).

    Article  ADS  Google Scholar 

  33. Xu, C. & Wu, C. Resonating plaquette phases in SU(4) Heisenberg antiferromagnet. Phys. Rev. B 77, 134449 (2008).

    Article  ADS  Google Scholar 

  34. Hermele, M., Gurarie, V. & Rey, A. M. Mott insulators of ultracold fermionic alkaline earth atoms: Underconstrained magnetism and chiral spin liquid. Phys. Rev. Lett. 103, 135301 (2009).

    Article  ADS  Google Scholar 

  35. Wu, C., Hu, J. P. & Zhang, S. C. Exact SO(5) symmetry in the spin-3/2 fermionic system. Phys. Rev. Lett. 91, 186402 (2003).

    Article  ADS  Google Scholar 

  36. Honerkamp, C. & Hofstetter, W. Ultracold fermions and the SU(N) Hubbard model. Phys. Rev. Lett. 92, 170403 (2004).

    Article  ADS  Google Scholar 

  37. Rapp, A., Hofstetter, W. & Zarand, G. Trionic phase of ultracold fermions in an optical lattice: A variational study. Phys. Rev. B 77, 144520 (2008).

    Article  ADS  Google Scholar 

  38. Affleck, I., Arovas, D. P., Marston, J. B. & Rabson, D. A. SU(2n) quantum antiferromagnets with exact C-breaking ground states. Nucl. Phys. B 366, 467–506 (1991).

    Article  ADS  MathSciNet  Google Scholar 

  39. Trotzky, S. et al. Time-resolved observation and control of superexchange interactions with ultracold atoms in optical lattices. Science 319, 295–299 (2008).

    Article  ADS  Google Scholar 

  40. Altman, E., Demler, E. & Lukin, M. D. Probing many-body states of ultracold atoms via noise correlations. Phys. Rev. A 70, 013603 (2004).

    Article  ADS  Google Scholar 

  41. Hofstetter, W., Cirac, J. I., Zoller, P., Demler, E. & Lukin, M. D. High-temperature superfluidity of fermionic atoms in optical lattices. Phys. Rev. Lett. 89, 220407 (2002).

    Article  ADS  Google Scholar 

  42. Werner, F., Parcollet, O., Georges, A. & Hassan, S. R. Interaction-induced adiabatic cooling and antiferromagnetism of cold fermions in optical lattices. Phys. Rev. Lett. 95, 056401 (2005).

    Article  ADS  Google Scholar 

  43. Schneider, U. et al. Metallic and insulating phases of repulsively interacting fermions in a 3D optical lattice. Science 322, 1520–1525 (2008).

    Article  ADS  Google Scholar 

  44. Fukuhara, T., Sugawa, S., Sugimoto, M., Taie, S. & Takahashi, Y. Mott insulator of ultracold alkaline-earth-metal-like atoms. Phys. Rev. A 79, 041604(R) (2009).

    Article  ADS  Google Scholar 

  45. Ni, K. K. et al. A high phase-space-density gas of polar molecules. Science 322, 231–235 (2008).

    Article  ADS  Google Scholar 

  46. Rey, A. M., Gorshkov, A. V. & Rubbo, C. Many-body treatment of the collisional frequency shift in fermionic atoms. Phys. Rev. Lett. 103, 260402 (2009).

    Article  ADS  Google Scholar 

  47. Cazalilla, M. A., Ho, A. F. & Ueda, M. Ultracold gases of ytterbium: Ferromagnetism and Mott states in an SU(6) Fermi system. New J. Phys. 11, 103033 (2009).

    Article  ADS  Google Scholar 

  48. Gorshkov, A. V., Jiang, L., Greiner, M., Zoller, P. & Lukin, M. D. Coherent quantum optical control with subwavelength resolution. Phys. Rev. Lett. 100, 093005 (2008).

    Article  ADS  Google Scholar 

  49. Ciuryło, R., Tiesinga, E. & Julienne, P. S. Optical tuning of the scattering length of cold alkaline-earth-metal atoms. Phys. Rev. A 71, 030701(R) (2005).

    Article  ADS  Google Scholar 

  50. Anderlini, M. et al. Controlled exchange interaction between pairs of neutral atoms in an optical lattice. Nature 448, 452–456 (2007).

    Article  ADS  Google Scholar 

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Acknowledgements

We gratefully acknowledge conversations with M. M. Boyd, A. J. Daley, S. Fölling, W. S. Bakr, J. I. Gillen, L. Jiang, G. K. Campbell, Y. Qi and N. Blümer. This work was supported by NSF, CUA, DARPA, the Packard Foundation, AFOSR MURI and NIST.

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Correspondence to A. V. Gorshkov.

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Gorshkov, A., Hermele, M., Gurarie, V. et al. Two-orbital S U(N) magnetism with ultracold alkaline-earth atoms. Nature Phys 6, 289–295 (2010). https://doi.org/10.1038/nphys1535

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