Title <研究ノート>擬一次元超伝導体(TMTSF)[2]ClO[4]の強磁場下における新奇な超伝導状態

Author(s) 米澤, 進吾

Citation 低温物質科学研究センター誌 : LTMセンター誌 (2009),15: 28-36

Issue Date 2009-12-01

URL https://doi.org/10.14989/153245

Right

Type Departmental Bulletin Paper

Textversion publisher

Kyoto University

=>#?bc@8(TMTSF)2ClO4AdC_e2345fghbc@ij

Anomalous superconducting state in strong magnetic fields observed in the quasi-one-dimensional superconductor (TMTSF)2ClO4

klmn � ^¡^¡¢Æ¡§¨©

Shingo Yonezawa Graduate School of Science, Kyoto University

We have revealed anomalous phenomena in the superconducting state of the quasi-one-dimensional

system (TMTSF)2ClO4 in precisely aligned high magnetic fields. The onset temperature of the superconductivity Tc

onset exhibits anomalous dependence on the magnetic field direction. The results are likely to be closely related to the Pauli paramagnetic pair-breaking effect and the field-induced dimensional crossover.

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1 1.2 1.4

b’ b’a abH // ab =5.0 kOe

10.0 kOe15.0 kOe20.0 kOe25.0 kOe30.0 kOe35.0 kOe40.0 kOe

0 0.2

T conse

t (K)

42.5 kOe

0 0.2

45.0 kOe

0 0.2

47.5 kOe

0 0.2

-90 -45 0 45 90 135 180* (degree)

49.0 kOe

(d)

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[1] H. K. Onnes, Koninklijke Nederlandsche Akademie van Wetenschappen Proceedings 14, 113 (1911); H. K. Onnes, ibid 14, 818 (1912).

[2] D. Jérome et al., J. Phys. Lett. 41, 95 (1980). [3] K. Bechgaard et al., Phys. Rev. Lett. 46, 852 (1981). [4] W. Zhang and C. A. R. Sá de Melo, Adv. Phys. 56, 545 (2007). [5] S. Yonezawa et al., Phys. Rev. Lett. 100, 117002 (2008). [6] S. Yonezawa et al., J. Phys. Soc. Jpn. 77, 054712 (2008). [7] D. L. Pevelen et al., Eur. Phys. J. B 19, 363 (2001). [8] S. Ishibashi, A. A. Manuel and M. Kohyama, J. Phys.: Condens. Matter 11, 2279 (1999). [9] I. J. Lee et al., Phys. Rev. Lett. 78, 3555 (1997). [10] J. I. Oh and M. J. Naughton, Phys. Rev. Lett. 92, 067001 (2004). [11] A. M. Clogston, Phys. Rev. Lett. 9, 266 (1962). [12] A. G. Lebed, JETP Lett. 44, 114 (1986). [13] A. G. Lebed, K. Machida and M. Ozaki, Phys. Rev. B 62, R795 (2000). [14] P. Fulde and R. A. Ferrell, Phys. Rev. 135, A550 (1964). [15] A. I. Larkin and Y. N. Ovchinnikov, Sov. Phys. JETP 20, 762 (1965). [16] Y. Matsuda and H. Shimahara, J. Phys. Soc. Jpn. 76, 051005 (2007). [17] N. Dupuis and G. Montambaux, Phys. Rev. B 49, 8993 (1994). [18] I. J. Lee et al., Phys. Rev. Lett. 88, 017004 (2001). [19] J. Shinagawa et al., Phys. Rev. Lett. 98, 147002 (2007). [20] S. Haddad et al., Phys. Rev. B 78, 075104 (2008). [21] S. Yonezawa et al., J. Phys.: Conf. Ser. 150, 052289 (2009). [22] K. Deguchi, T. Ishiguro and Y. Maeno, Rev. Sci. Instrum. 75, 1188 (2004). [23] M. J. Naughton et al., Synth. Met. 85, 1481 (1997). ~���#

kl mn »Shingo YONEZAWAÀ � ^¡^¡¢Æ¡§¨© ïÆ¡]�¡ïÆ¡�� u� »º86-ïY§¨V Tel: 075-753-3744À yonezawa@scphys.kyoto-u.ac.jp 2005& 3' � ^¡Æ¡%i 2008& 3' � ^¡Æ¡�i 2008& 4' � ^¡^¡¢Æ¡§¨© �i§¨� 2008& 7'çâצ

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