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Observation of the spin Seebeck effect

Naturevolume 455, pages778–781 (2008)Cite this article

Abstract

The generation of electric voltage by placing a conductor in a temperature gradient is called the Seebeck effect1,2. Its efficiency is represented by the Seebeck coefficient,S, which is defined as the ratio of the generated electric voltage to the temperature difference, and is determined by the scattering rate and the density of the conduction electrons. The effect can be exploited, for example, in thermal electric-power generators and for temperature sensing, by connecting two conductors with different Seebeck coefficients, a device called a thermocouple1,2. Here we report the observation of the thermal generation of driving power, or voltage, for electron spin: the spin Seebeck effect. Using a recently developed spin-detection technique that involves the spin Hall effect3,4,5,6,7,8,9,10,11,12,13,14, we measure the spin voltage generated from a temperature gradient in a metallic magnet. This thermally induced spin voltage persists even at distances far from the sample ends, and spins can be extracted from every position on the magnet simply by attaching a metal. The spin Seebeck effect observed here is directly applicable to the production of spin-voltage generators, which are crucial for driving spintronic15,16,17,18 devices. The spin Seebeck effect allows us to pass a pure spin current19, a flow of electron spins without electric currents, over a long distance. These innovative capabilities will invigorate spintronics research.

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Figure 1:The spin Seebeck effect.
Figure 2:Experimental set-up.
Figure 3:Measurements of electromotive force.
Figure 4:Dependence on magnetic field angle and position of Pt wire.

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References

  1. Ashcroft, N. W. & Mermin, N. D.Solid State Physics 253–258 (Saunders College, 1976)

    Google Scholar 

  2. Maekawa, S. et al.Physics of Transition Metal Oxides 323–331 (Springer, 2004)

    Book  Google Scholar 

  3. Dyakonov, M. I. & Perel, V. I. Current-induced spin orientation of electrons in semiconductors.Phys. Lett. A35, 459–460 (1971)

    Article ADS  Google Scholar 

  4. Hirsch, J. E. Spin Hall effect.Phys. Rev. Lett.83, 1834–1837 (1999)

    Article ADS CAS  Google Scholar 

  5. Takahashi, S. & Maekawa, S. Hall effect induced by a spin-polarized current in superconductors.Phys. Rev. Lett.88, 116601 (2002)

    Article ADS CAS  Google Scholar 

  6. Murakami, S., Nagaosa, N. & Zhang, S.-C. Dissipationless quantum spin current at room temperature.Science301, 1348–1351 (2003)

    Article ADS CAS  Google Scholar 

  7. Sinova, J. et al. Universal intrinsic spin Hall effect.Phys. Rev. Lett.92, 126603 (2004)

    Article ADS  Google Scholar 

  8. Kato, Y. K., Myers, R. C., Gossard, A. C. & Awschalom, D. D. Observation of the spin Hall effect in semiconductors.Science306, 1910–1913 (2004)

    Article ADS CAS  Google Scholar 

  9. Wunderlich, J., Kaestner, B., Sinova, J. & Jungwirth, T. Experimental observation of the spin-Hall effect in a two-dimensional spin-orbit coupled semiconductor system.Phys. Rev. Lett.94, 047204 (2005)

    Article ADS CAS  Google Scholar 

  10. Saitoh, E., Ueda, M., Miyajima, H. & Tatara, G. Conversion of spin current into charge current at room temperature: Inverse spin-Hall effect.Appl. Phys. Lett.88, 182509 (2006)

    Article ADS  Google Scholar 

  11. Valenzuela, S. O. & Tinkham, M. Direct electronic measurement of the spin Hall effect.Nature442, 176–179 (2006)

    Article ADS CAS  Google Scholar 

  12. Kimura, T., Otani, Y., Sato, T., Takahashi, S. & Maekawa, S. Room-temperature reversible spin Hall effect.Phys. Rev. Lett.98, 156601 (2007)

    Article ADS CAS  Google Scholar 

  13. Seki, T. et al. Giant spin Hall effect in perpendicularly spin-polarized FePt/Au devices.Nature Mater.7, 125–129 (2008)

    Article ADS CAS  Google Scholar 

  14. Takahashi, S. & Maekawa, S. Spin current in metals and superconductors.J. Phys. Soc. Jpn77, 031009 (2008)

    Article ADS  Google Scholar 

  15. Wolf, S. A. et al. Spintronics: a spin-based electronics vision for the future.Science294, 1488–1495 (2001)

    Article ADS CAS  Google Scholar 

  16. Žutić, I., Fabian, J. & Das Sarma, S. Spintronics: fundamentals and applications.Rev. Mod. Phys.76, 323–410 (2004)

    Article ADS  Google Scholar 

  17. Maekawa, S. (ed.)Concepts in Spin Electronics (Oxford Univ. Press, 2006)

    Book  Google Scholar 

  18. Chappert, C., Fert, A. & Van Dau, F. N. The emergence of spin electronics in data storage.Nature Mater.6, 813–823 (2007)

    Article ADS CAS  Google Scholar 

  19. Slonczewski, J. C. Conductance and exchange coupling of two ferromagnets separated by a tunneling barrier.Phys. Rev. B39, 6995–7002 (1989)

    Article ADS CAS  Google Scholar 

  20. Valet, T. & Fert, A. Theory of the perpendicular magnetoresistance in magnetic multilayers.Phys. Rev. B48, 7099–7113 (1993)

    Article ADS CAS  Google Scholar 

  21. Cadeville, M. C. & Roussel, J. Thermoelectric power and electronic structure of dilute alloys of nickel and cobalt with d transition elements.J. Phys. F1, 686–710 (1971)

    Article ADS CAS  Google Scholar 

  22. Gravier, L., Serrano-Guisan, S., Reuse, F. & Ansermet, J.-P. Thermodynamic description of heat and spin transport in magnetic nanostructures.Phys. Rev. B73, 024419 (2006)

    Article ADS  Google Scholar 

  23. Tsyplyatyev, O., Kashuba, O. & Fal’ko, V. I. Thermally excited spin current and giant magnetothermopower in metals with embedded ferromagnetic nanoclusters.Phys. Rev. B74, 132403 (2006)

    Article ADS  Google Scholar 

  24. Hatami, M., Bauer, G. E. W., Zhang, Q.-F. & Kelly, P. J. Thermal spin-transfer torque in magnetoelectronic devices.Phys. Rev. Lett.99, 066603 (2007)

    Article ADS  Google Scholar 

  25. Bass, J. & Pratt, W. P. Spin-diffusion lengths in metals and alloys, and spin-flipping at metal/metal interfaces: an experimentalist’s critical review.J. Phys. Condens. Matter19, 183201 (2007)

    Article ADS  Google Scholar 

  26. Callen, H. B.Thermodynamics Ch. 17 (Wiley, 1960)

    MATH  Google Scholar 

  27. Hirohata, A., Xu, Y. B., Guertler, C. M., Bland, J. A. C. & Holmes, S. N. Spin-polarized electron transport in ferromagnet/semiconductor hybrid structures induced by photon excitation.Phys. Rev. B63, 104425 (2001)

    Article ADS  Google Scholar 

  28. Jedema, F. J., Filip, A. T. & van Wees, B. J. Electrical spin injection and accumulation at room temperature in an all-metal mesoscopic spin valve.Nature410, 345–348 (2001)

    Article ADS CAS  Google Scholar 

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Acknowledgements

The authors thank Y. Suzuki, S. E. Barnes, Y. Fujitani, G. Tatara, K. M. Itoh, H. Kuwahara and M. Matoba for discussions. This work was supported by a Grant-in-Aid for Scientific Research in Priority Area ‘Creation and control of spin current’ (19048028) from MEXT, Japan, a Grant-in-Aid for Encouragement of Young Scientists (A) from MEXT, Japan, the global COE for the ‘High-level global cooperation for leading-edge platform on access spaces’ from MEXT, Japan, a Strategic Information and Communications R&D Promotion Programme from MIC, Japan, and the Next Generation Supercomputing Project of Nanoscience Program from IMS, Japan.

Author information

Authors and Affiliations

  1. Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan

    K. Uchida, K. Harii, K. Ando & E. Saitoh

  2. Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan

    S. Takahashi, J. Ieda & S. Maekawa

  3. CREST, Japan Science and Technology Agency, Sanbancho, Tokyo 102-0075, Japan ,

    S. Takahashi, J. Ieda & S. Maekawa

  4. Cross-Correlated Materials Research Group, RIKEN, Wako, Saitama 351-0198, Japan ,

    W. Koshibae

  5. PRESTO, Japan Science and Technology Agency, Sanbancho, Tokyo 102-0075, Japan ,

    E. Saitoh

Corresponding author

Correspondence toE. Saitoh.

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Uchida, K., Takahashi, S., Harii, K.et al. Observation of the spin Seebeck effect.Nature455, 778–781 (2008). https://doi.org/10.1038/nature07321

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Editorial Summary

Thermospintronics: spintronics just got hotter

In 1821, Thomas Johann Seebeck found that electricity is generated from heat: the thermoelectric or Seebeck effect is used to generate electric power and also in the thermocouple, commonly used for temperature sensing. In the thermocouple two pieces of metal with different Seebeck coefficients, which determine the ratio of generated voltage to the temperature difference, are connected to each other. In theory there should be a 'spintronic' equivalent of the thermocouple — and now there is one in practice. Uchida et al. used a recently developed spin detection technique based on the spin Hall effect to demonstrate the spin-Seebeck effect for the first time, using it to obtain pure spin currents, a flow of spins without electric currents, over millimetre distances. The spin-Seebeck effect can generate the 'spin power' to drive spintronic devices, opening the way to the development of thermospintronics.

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