Abstract
We performed SQUID-NMR measurements on a rhodium single crystal at ultra-low nuclear-spin temperatures. With initial polarizations up to p=0.95, the antiferromagnetic tendency was clear, but surprisingly no indication of actual nuclear magnetic ordering was obtained. The lowest nuclear temperatures achieved were below 100 pK, whereas the lowest directly measured temperature was 280 pK. Double-spin-flip and evidence for triple-spin-flip resonance lines were detected, yielding direct information of the interactions between the nuclear spins. The superconducting transition of rhodium was observed with the critical values, Tc=210 μK and Bc(0)=3.4 μT. For the first time, measurements with substantially correlated nuclei were performed in the superconducting state, where the effect of the coherent electron system on the spin-lattice relaxation rate was studied. The spin-lattice relaxation time was longer in the superconducting state at all temperatures and displayed a strong dependence on nuclear susceptibility.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
REFERENCES
A. S Oja and O. V. Lounasmaa, Nuclear magnetic ordering in simple metals at positive and negative temperatures, Rev. Mod. Phys. 69, 1–136 (1997).
M. T. Huiku and M. T. Loponen, Observation of a magnetic phase transition in the nuclear spin system of metallic copper at nanokelvin temperatures, Phys. Rev. Lett. 49, 1288–1291 (1982).
P. J. Hakonen, S. Yin, and K. K. Nummila, Phase diagram and NMR studies of antiferro-magnetically ordered polycrystalline silver, Europhys. Lett. 15, 677–682 (1991).
Ch. Buchal, F. Pobell, R. M. Mueller, M. Kubota, and J. R. Owers-Bradley, Superconduc-tivity of rhodium at ultralow temperatures, Phys. Rev. Lett. 50, 64–67 (1983).
D. E. MacLaughlin, in Solid State Physics, H. Ehrenreich, F. Seitz, and D. Turnbull (eds.), Vol. 31, Academic, New York (1976).
S. Rehmann, T. Herrmannsdörfer, and F. Pobell, Interplay of nuclear magnetism and superconductivity in AuIn2, Phys. Rev. Lett. 78, 1122–1125 (1997).
M. Seibold, T. Herrmannsdörfer, and F. Pobell, Static nuclear magnetisation of aluminum measured by its influence on the superconducting critical field, J. Low Temp. Phys. 110, 363–368 (1998).
R. T. Vuorinen, P. J. Hakonen, W. Yao, and O. V. Lounasmaa, Susceptibility and relaxation measurements on rhodium metal at positive and negative spin temperatures in the nanokelvin range, J. Low Temp. Phys. 98, 449–487 (1995).
P. J. Hakonen, R. T. Vuorinen, and J. E. Martikainen, Nuclear antiferromagnetism in rhodium metal at positive and negative nanokelvin temperatures, Phys. Rev. Lett. 70, 2818–2821 (1993).
A. S. Oja and P. Kumar, Indirect nuclear spin interactions and nuclear ordering in metals, J. Low Temp. Phys. 66, 155–167 (1987).
A. Narath, A. T. Fromhold, Jr, and E. D. Jones, Nuclear spin relaxation in metals: Rhodium, palladium, and silver, Phys. Rev. 144, 428–435 (1966).
J. T. Tuoriniemi, T. A. Knuuttila, K. Lefmann, K. K. Nummila, W. Yao, and F. B. Rasmussen, Double-spin-flip resonance of rhodium nuclei at positive and negative spin temperatures, Phys. Rev. Lett. 84, 370–373 (2000).
N. W. Ashcroft and N. D. Mermin, Solid State Physics, Holt, Rinehart and Winston, New York (1976).
W. Yao, T. A. Knuuttila, K. K. Nummila, J. E. Martikainen, A. S. Oja, and O. V. Lounasmaa, A versatile nuclear demagnetization cryostat for ultralow temperature research, J. Low Temp. Phys. 120, 121–150 (2000).
Material-Technologie 6 Kristalle GmbH, Im Langenbroich 20, D-52428 Jülich.
J. A. Osborn, Demagnetizing factors of the general ellipsoid, Phys. Rev. 67, 351–357 (1945).
F. R. Fickett, Oxygen annealing of copper: A review, Materials Science and Engineering 14, 199–210 (1974).
A. C. Ehrlich, Oxygen annealing of silver for obtaining low electrical resistivity: Technique and interpretation, J. Mater. Sci. 9, 1064–1072 (1974).
F. Pobell, Matter and Methods at Low Temperatures, Springer-Verlag (1992).
K. Lefmann, T. A. Knuuttila, J. E. Martikainen, L. T. Kuhn, and K. K. Nummila, Effect of heat treatment of pure and carbon-polluted rhodium samples on the low-temperature resistivity, J. Mater. Sci. 36, 839–844 (2001).
Vacuumschmelze GmbH, Grüner Weg 37, 63450, Hanau, Germany.
P. Jauho and P. V. Pirilä, Spin-lattice relaxation of nuclei due to conduction electrons at very low temperatures, Phys. Rev. B 1, 21–24 (1970).
P. J. Hakonen, S. Yin, and O. V. Lounasmaa, Nuclear magnetism in silver at positive and negative absolute temperatures in the low nanokelvin range, Phys. Rev. Lett. 64, 2707–2710 (1990).
Oxford Instruments, Ltd. Old Station Way, Eynsham OX8 1TL, UK.
VTT Automation, Otakaari 7 B, P.O. Box 1304, FIN-02044 VTT, Finland.
M. Goldman, Spin Temperature and Nuclear Magnetic Resonance in Solids, Oxford University Press (1970).
H. Ishii and P. J. Hakonen, Nuclear spin relaxation at ultralow temperatures, Phys. Rev. B 59, 9462–9466 (1999).
A. S. Oja, A. J. Annila, and Y. Takano, Investigations of nuclear magnetism in silver down to picokelvin temperatures. I, J. Low Temp. Phys. 85, 1–24 (1991).
A. G. Anderson, Nuclear spin absorption spectra in solids, Phys. Rev. 125, 1517–1527 (1962).
K. I. Juntunen, Effects of eddy currents on the NMR spectra of a highly polarized metal sample, Master's thesis, Helsinki University of Technology (2000).
P. J. Hakonen and S. Yin, Investigations of nuclear magnetism in silver down to picokelvin temperatures. II, J. Low Temp. Phys. 85, 25–65 (1991).
J. P. Ekström, J. F. Jacquinot, M. T. Loponen, J. K. Soini, and P. Kumar, Nuclear spin interaction in copper: NMR at high polarization and in low fields, Physica B 98, 45–52 (1979).
P. L. Moyland, P. Kumar, J. Xu, and Y. Takano, Coupling of the Larmor precession to the correlated motion of pairs of nuclear spins in noble metals, Phys. Rev. B 48, 14020–14022 (1993).
H. Cheng, Spin absorption of solids, Phys. Rev. 124, 1359–1367 (1961).
A. G. Anderson, Nonresonant nuclear spin absorption in lithium, sodium, and aluminium, Phys. Rev. 115, 863–868 (1959).
Yong-Jihn Kim and A. W. Overhauser, Magnetic impurities in superconductors: A theory with different predictions, Phys. Rev. B 49, 15799–15812 (1994).
L. C. Hebel and C. P. Slichter, Nuclear spin relaxation in normal and superconducting aluminum, Phys. Rev. 113, 1504–1519 (1959).
T. A. Knuuttila, J. T. Tuoriniemi, and K. Lefmann, Relaxation of polarized nuclei in superconducting rhodium, Phys. Rev. Lett. 85, 2573–2576 (2000).
K. K. Nummila, J. T. Tuoriniemi, R. T. Vuorinen, K. Lefmann, A. Metz, and F. B. Rasmussen, Neutron diffraction studies of nuclear magnetic ordering in silver, J. Low Temp. Phys. 112, 73–116 (1998).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Knuuttila, T.A., Tuoriniemi, J.T., Lefmann, K. et al. Polarized Nuclei in Normal and Superconducting Rhodium. Journal of Low Temperature Physics 123, 65–102 (2001). https://doi.org/10.1023/A:1017545531677
Issue Date:
DOI: https://doi.org/10.1023/A:1017545531677