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Magnetic Quantum Tunnelling in Faster Relaxation Process in Mn12Ac Molecular Magnets |
| LIU Hai-Qing;SU Shao-Kui;JING Xiu-Nian;LIU Ying;HE Lun-Hua;GE Pei-Wen;YAN Qi-Wei;WANG Yun-Ping |
| Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, PO Box 603, Beijing 100080 |
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LIU Hai-Qing, SU Shao-Kui, JING Xiu-Nian et al 2007 Chin. Phys. Lett. 24 532-535 |
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Abstract The field-tuned ac susceptibility of Mn12Ac single crystal has been measured as functions of temperature and frequency. Two relaxation processes appear in our measurement. One is related to the magnetic quantum tunnelling of a collective spin S=12 by a 61K magnetic barrier and it has been well studied, while the other is faster than the former and its mechanism is unclear. We find that the relaxation time for the faster process shows the minima at H=0 and H=3.4kOe, indicating that the quantum tunnelling also takes place in this process while the resonant fields are different from what we have known before.
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75.45.+j
75.50.Xx
73.43.Jn
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Received: 20 September 2006
Published: 24 February 2007
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[1] Enz M and Schilling R 1986 J. Phys. C 19 1765
[2] van Hemmen J L and Suto A 1986 Europhys. Lett. 1 481
[3] Chudnovsky E M and Gunther L 1988 Phys. Rev. Lett. 60 661
[4] Tejada J, Zhang X X and Balcells L 1993 J. Appl. Phys. 73 6709
[5] Barbara B, Sampaio L C, Wegrowe J E, Ratnam B A, MarchandA, Paulsen C, Novak M A, Tholence J L, Uehara M and Fruchart D 1993 J. Appl. Phys. 73 6703
[6] Barbara B, Wernsdorfer W, Sampaio L C, Park J G, Paulsen C,Novak M A, Ferre R, Mailly D, Sessoli R, Caneschi A, Hasselbach K,Benoit A and Thomas L 1995 J. Magn. Magn. Mater. 140-144 1825
[7] Awschalom D D, Divincenzo D P and Smyth J F 1992 Science 258 414
[8] Friedman J R, Sarachik M P, Tejada J and Ziolo R 1996 Phys. Rev. Lett. 76 3830
[9] Sangregorio C, Ohm T, Paulsen C, Sessoli R and Gatteschi D1997 Phys. Rev. Lett. 78 4645
[10] Wernsdorfer W and Sessoli R 1999 Science 284 133
[11] Paulsen C and Park J G 1995 Quantum Tunnelingof Magnetization ed Gunther L and Barbara B (Dordrecht: Kluwer) p 189
[12] Lis T 1980 Acta Crystallogr. B 36 2042
[13] Caneschi A, Gatteschi D, Sessoli R, Barra A L, Brunel L Cand Guillot M 1991 J. Am. Chem. Soc. 113 5837
[14] Chiorescu I, Giraud R, Jansen A G M, Caneschi A and Barbara B2000 Phys. Rev. Lett. 85 4807
[15] Luis F, Bartolome J, Fernandez J F, Tejada J and Hernandez JM 1997 Phys. Rev. B 55 11448
[16] Barbara B, Thomas L, Lionti F, Chiorescu I and Sulpice A 1999 J. Magn. Magn. Mater. 200 167
[17] Brown W F 1959 J. Appl. Phys. 30 1308
[18] Villain J, Hartmann-Boutron F, Sessoli R and Rettori A 1994 Europhy. Lett. 27 159
[19] Politi P, Rettori A, Hartmann-Boutron F and Villain J 1995 Phys. Rev. Lett. 75 537
[20] Liu H Q and Wang Y P 2005 Chin. Phys. Lett. 22 3166
[21] Auhin S M J, Sun Z, Eppley H J, Ramberger E M, Guzei I A,Folting K, Gantzel P K, Rheingold A L, Christou G and Hendrickson D N2001 Polyhedron 20 1139 |
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