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Journal of Low Temperature Physics

, Volume 187, Issue 1–2, pp 43–53 | Cite as

Dynamic Nuclear Polarization and Relaxation of H and D Atoms in Solid Mixtures of Hydrogen Isotopes

  • S. Sheludiakov
  • J. Ahokas
  • J. Järvinen
  • O. Vainio
  • L. Lehtonen
  • S. Vasiliev
  • D. M. Lee
  • V. V. Khmelenko
Article

Abstract

We report on a study of dynamic nuclear polarization and electron and nuclear spin relaxation of atomic hydrogen and deuterium in solid molecular matrices of \(\hbox {H}_{2}, \hbox {D}_{2}\), and HD mixtures. The electron and nuclear spin relaxation times (\(T_{1\mathrm{e}}\) and \(T_{1\mathrm{N}}\)) were measured within the temperature range 0.15–2.5 K in a magnetic field of 4.6 T, conditions which ensure a high polarization of electron spins. We found that \(T_{1\mathrm{e}}\) is nearly temperature independent in this temperature range, while \(T_{1\mathrm{N}}\) decreased by two orders of magnitude upon raising temperature. Such strong temperature dependence is typical for the nuclear Orbach mechanism of relaxation via the electron spins. We found that the nuclear spins of H atoms in solid \(\hbox {D}_{2}\) and \(\hbox {D}_{2}{:}\hbox {HD}\) can be efficiently polarized by the Overhauser effect. Pumping the forbidden transitions of H atoms also leads to DNP, with the efficiency strongly dependent on the concentration of D atoms. This behavior indicates the cross effect mechanism of the DNP and nuclear relaxation, which turns out to be well resolved in the conditions of our experiments. Efficient DNP of H atoms was also observed when pumping the middle D line located in the center of the ESR spectrum. This phenomenon can be explained in terms of clusters or pairs of H atoms with a strong exchange interaction. These clusters have partially allowed transitions in the center of the ESR spectrum, and DNP may be created via the resolved cross effect.

Keywords

Hydrogen Deuterium Electron spin resonance Dynamic nuclear polarization 

Notes

Acknowledgements

We acknowledge the funding from the Wihuri Foundation and the Academy of Finland Grants Nos. 258074, 260531 and 268745. This work is also supported by NSF Grant No DMR 1209255. S.S. thanks UTUGS for support.

References

  1. 1.
    S. Sheludiakov, J. Ahokas, J. Järvinen, D. Zvezdov, O. Vainio, L. Lehtonen, S. Vasiliev, S. Mao, V.V. Khmelenko, D.M. Lee, Dynamic nuclear polarization of high-density atomic hydrogen in solid mixtures of molecular hydrogen isotopes. Phys. Rev. Lett. 113, 265303 (2014)ADSCrossRefGoogle Scholar
  2. 2.
    A.W. Overhauser, Polarization of nuclei in metals. Phys. Rev. 92, 411 (1953)ADSCrossRefzbMATHGoogle Scholar
  3. 3.
    T.V. Can, M.A. Caporini, F. Mentink-Vigier, B. Corzilius, J.J. Walish, M. Rosay, W.E. Maas, M. Baldus, S. Vega, T.M. Swager, R.G. Griffin, Overhauser effects in insulating solids. J. Chem. Phys. 141(6), 064202 (2014)ADSCrossRefGoogle Scholar
  4. 4.
    A.E. Dementyev, D.G. Cory, C. Ramanathan, High-field Overhauser dynamic nuclear polarization in silicon below the metal–insulator transition. J. Chem. Phys. 134(15), 154511 (2011)ADSCrossRefGoogle Scholar
  5. 5.
    T. Maly, G.T. Debelouchina, V.S. Bajaj, K.N. Hu, C.G. Joo, M.L. Mak-Jurkauskas, J.R. Sirigiri, P.C.A. van der Wel, J. Herzfeld, R.J. Temkin, R.G. Griffin, Dynamic nuclear polarization at high magnetic fields. J. Chem. Phys. 128(5), 052211 (2008)ADSCrossRefGoogle Scholar
  6. 6.
    V.A. Atsarkin, A.V. Kessenikh, Dynamic nuclear polarization in solids: the birth and development of the many-particle concept. Appl. Magn. Reson. 43(1), 7 (2012)CrossRefGoogle Scholar
  7. 7.
    D.S. Wollan, Dynamic nuclear polarization with an inhomogeneously broadened ESR line. I. Theory. Phys. Rev. B 13, 3671 (1976)ADSCrossRefGoogle Scholar
  8. 8.
    G. Feher, E.A. Gere, Electron spin resonance experiments on donors in silicon. II. Electron spin relaxation effects. Phys. Rev. 114, 1245 (1959)ADSCrossRefGoogle Scholar
  9. 9.
    H. Honig, E. Stupp, Electron spin–lattice relaxation in phosphorus-doped silicon. Phys. Rev. Lett. 1, 275 (1958)ADSCrossRefGoogle Scholar
  10. 10.
    A. Abragam, M. Goldman, Nuclear Magnetism: Order and Disorder (Clarendon Press, Oxford, 1982)Google Scholar
  11. 11.
    D. Pines, J. Bardeen, C.P. Slichter, Nuclear polarization and impurity-state spin relaxation processes in silicon. Phys. Rev. 106, 489 (1957)ADSCrossRefGoogle Scholar
  12. 12.
    D.A. Tayurskii, Cross-relaxation in paramagnetic crystals at low temperatures. Phys. B: Condens. Matter 165, 231 (1990)ADSGoogle Scholar
  13. 13.
    A. Katunin, I. Lukashevich, S. Orosmamatov, V. Sklyarevskii, V. Suraev, V. Filippov, N. Fivippov, V. Shevtsov, The Overhauser effect for atomic hydrogen in a solid H\(_2\)-matrix. Phys. Lett. 87A(9), 483 (1982)ADSCrossRefGoogle Scholar
  14. 14.
    J. Järvinen, J. Ahokas, S. Sheludyakov, O. Vainio, L. Lehtonen, S. Vasiliev, D. Zvezdov, Y. Fujii, S. Mitsudo, T. Mizusaki, M. Gwak, S. Lee, S. Lee, L. Vlasenko, Efficient dynamic nuclear polarization of phosphorus in silicon in strong magnetic fields and at low temperatures. Phys. Rev. B 90, 214401 (2014)ADSCrossRefGoogle Scholar
  15. 15.
    S. Sheludiakov, J. Ahokas, O. Vainio, J. Järvinen, D. Zvezdov, S. Vasiliev, V.V. Khmelenko, S. Mao, D.M. Lee, Experimental cell for molecular beam deposition and magnetic resonance studies of matrix isolated radicals at temperatures below 1 K. Rev. Sci. Instrum. 85(5), 053902 (2014)ADSCrossRefGoogle Scholar
  16. 16.
    J. Ahokas, O. Vainio, J. Järvinen, V.V. Khmelenko, D.M. Lee, S. Vasiliev, Stabilization of high-density atomic hydrogen in H\(_2\) films at T \(<\) 0.5 K. Phys. Rev. B 79(22), 220505 (2009)ADSCrossRefGoogle Scholar
  17. 17.
    S. Sheludiakov, J. Ahokas, J. Järvinen, D. Zvezdov, L. Lehtonen, O. Vainio, S. Vasiliev, D.M. Lee, V.V. Khmelenko, Tunneling chemical exchange reaction D \(+\) HD \(\rightarrow \) D\(_2+\) H in solid HD and D2 at temperatures below 1 K. Phys. Chem. Chem. Phys. 18, 29600 (2016)Google Scholar
  18. 18.
    G.W. Collins, J.L. Maienschein, E.R. Mapoles, R.T. Tsugawa, E.M. Fearon, P.C. Souers, J.R. Gaines, P.A. Fedders, Atomic ESR relaxation in tritiated solid hydrogen. Phys. Rev. B 48, 12620 (1993)ADSCrossRefGoogle Scholar
  19. 19.
    E.P. Bernard, R.E. Boltnev, V.V. Khmelenko, V. Kiryukhin, S.I. Kiselev, D.M. Lee, Deuterium atoms and molecules in nanoclusters of molecular deuterium. Phys. Rev. B 69, 104201 (2004)ADSCrossRefGoogle Scholar
  20. 20.
    Y.A. Dmitriev, EPR study of H and D atoms in quench-condensed solid D\(_2\). J. Low Temp. Phys. 180(3), 284 (2015)ADSCrossRefGoogle Scholar
  21. 21.
    M. Sharnoff, R.V. Pound, Magnetic resonance studies of unpaired atoms in solid \({\rm D}_{2}\). Phys. Rev. 132, 1003 (1963)ADSCrossRefGoogle Scholar
  22. 22.
    J.V. Houten, W. Wenckebach, N. Poulis, A study of the thermal contact between the nuclear Zeeman system and the electron dipole–dipole interaction system. Phys. B+C 92(2), 210 (1977)Google Scholar
  23. 23.
    G. Feher, R.C. Fletcher, E.A. Gere, Exchange effects in spin resonance of impurity atoms in silicon. Phys. Rev. 100, 1784 (1955)ADSCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • S. Sheludiakov
    • 1
  • J. Ahokas
    • 1
  • J. Järvinen
    • 1
  • O. Vainio
    • 1
  • L. Lehtonen
    • 1
  • S. Vasiliev
    • 1
  • D. M. Lee
    • 2
  • V. V. Khmelenko
    • 2
  1. 1.Wihuri Physical Laboratory, Department of Physics and AstronomyUniversity of TurkuTurkuFinland
  2. 2.Department of Physics and Astronomy, Institute for Quantum Science and EngineeringTexas A&M UniversityCollege StationUSA

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