Quantum tunneling effect in magnetic particles

Current Opinion in Solid State and Materials Science

Volumn 2, Issue 2, 1997, Pages 220-225

  Barbara, Bernard ^a   Wernsdorfer, Wolfgang ^a  

^a LABORATOIRE DE CRISTALLOGRAPHIE   (France)

Author keywords

DWJ domain wall junction; MFM magnetic force microscopy; MQC macroscopic quantum coherence; MQT macroscopic quantum tunneling; QTM quantum tunneling of magnetization; Rms square root of the mean deviation; SQUID superconducting quantum interference device

Indexed keywords

EID: 0040647696     PISSN: 13590286     EISSN: None     Source Type: Journal    
DOI: 10.1016/s1359-0286(97)80069-1     Document Type: Article

References (56)

1. Leggett AJ, Chakravarty S, Dorsey AT, Fisher MPA, Garg A, Zwerger W. Dynamics of the dissipative two-state system. Rev Mod Phys. 59:1987;1-84.
2. Clarke J, Cleland AN, Devoret MH, Esteve D, Martinis JM. Quantum mechanics of a macroscopic variable: the phase difference of a Josephson junction. Science. 239:1988;992-997.
3. Van Hemmen JL, Sütöts A. Tunnelling of quantum spins. Europhys Lett. 1:1986;481-490.
4. Chudnovsky EM, Gunther L. Quantum tunneling of magnetization in small ferromagnetic particles. Phys Rev Lett. 60:1988;661-664.
5. Barbara B, Chudnovsky EM. Macroscopic quantum tunneling in antiferromagnets. Phys Lett A. 145:1990;205-208.
6. Stamp PCE, Chudnovsky EM, Barbara B. Quantum tunneling of magnetization in solids. Int J Mod Phys. 6:1992;1355-1478.
7. Prokofev NV, Stamp PCE. Quantum relaxation of magnetization in magnetic particles. J Low Temp Phys. 104:1996;143-209.
8. Gunther L, Barbara B. Quantum tunneling of magnetisation. 301:1995;Kluwer, Dordrecht, These Proceedings include 29 articles that represent the contribution of the participants in the NATO Advanced Workshop on Quantum Tunneling of Magnetization, held in Chichilianne, France.
9. Tejada J, Zhang X. Experiments in quantum magnetic relaxation. J Mag Mag Mat. 140-144:1995;1815-1818.
10. Barbara B, Wernsdorfer W, Sampaio LC, Park JG, Paulsen C, Novak MA, Ferré R, Mailly D, Sessoli R, Caneschi A, et al. Mesoscopic quantum tunneling of the magnetization. J Mag Mag Mat. 140-144:1995;1825-1828.
11. Ibrahim MM, Darwish S, Seehra MS. Nonlinear temperature variation of magnetic viscosity in nanoscale FeOOH particles. Phys Rev B. 51:1995;2955-2959.
12. Sappey R, Vincent E, Hammann J, Chaput F, Boilot JP, Zins D. Anomalies in the relaxation of small magnetic particles at very low temperatures. Hadjipanayis HJ. Magnetic Hysteresis in Novel Magnetic Materials. 1997;Kluwer Academic Publisher, Greece.
13. Yamazaki H, Tatara G, Katsumata K, Ishibashi K, Aoyagi Y. Magnetic relaxation in Ni wires. J Mag Mag Mat. 156:1996;135-136.
14. O'Shea MJ, Perera P. Influence of nanostructure on magnetic properties of strong anisotropy systems. J Mag Mag Mat. 156:1996;141-142.
15. Zhang XX, Hernandez JM, Tejada J, Ziolo RF. Magnetic properties, relaxation, and quantum tunneling in CoFe204 nanoparticles embedded in potassium silicate. Phys Rev B. 54:1996;4101-4106.
16. Barbara B, Paulsen C, Sampaio LC, Uehara M, Fruchard F, Tholence JL, Marchand A. Observation of quantum tunnelling of the magnetization vector in small particles with or without domain walls. Dormann JL. Proceedings of the International Workshop Studies of Magnetic Properties of Fine Particles: 1991; Rome. 1992;235-242 Elsevier, D. Amsterdam.
17. Barbara B, Gunther L. The barrier plot as a tool in magnetic relaxation studies. J Mag Mag Mat. 128:1993;35-41.
18. Barbara B, Sampaio LC, Marchand A, Kubo O, Takeuchi H. Two-variables scaling of the magnetic viscosity in Ba-ferrite nanoparticles. J Mag Mag Mat. 136:1994;183-188.
19. Ferré R, Barbara B. Magnetization studies of disordered systems: importance of adiabaticity in nonequilibrium processes. J Mag Mag Mat. 140-144:1995;1861-1862.
20. Ribas R, Labarta A. Magnetic relaxation of a one-dimensional model for small particle systems with dipolar interaction: Monte Carlo simulation. J Appl Phys. 80:1996;5192-5199.
21. Kodama RH, Berkowitz AE, McNiff EJ Jr, Foner S. Surface spin disorder in NiFe204 Nanoparticles. Phys Rev Lett. 77:1996;394-397 The authors present anomalous magnetic properties at low temperatures of nickel ferrite nanoparticles. They propose a model of magnetization within these particles consisting of ferrimagnetically aligned core spins and a spin-glass-like surface layer. Calculation of the energy barrier distribution between surface spin states is consistent with n(E) ∞ 1/E which has been shown to produce a thermally activated temperature-independent viscosity [16].
22. Gunther L. On the search for qauntum tunneling of magnetization. Gunther L, Barbara B. Quantum tunneling of magnetisation. 413-434:1995;301 Kluwer, Dordrecht. [NATO ASI Series E: Applied Sciences].
23. Lederman M, Gibson GA, Schultz S. Observation of thermal switching of a single ferromagnetic particle. J Appl Phys. 73:1993;6961-6963.
24. Chang T, Zhu JG. Angular dependence measurement of individual barium ferrite recording particles near the single domain size. J Appl Phys. 75:1994;5553-5555.
25. Wernsdorfer W, Hasselbach K, Mailly D, Barbara B, Benoit A, Thomas L, Suran G. DC-SQUID magnetization measurements of single magnetic particles. J Mag Mag Mat. 145:1995;33-39 The authors present the first magnetization measurements of single submicronic particles at very low temperatures made of either Ni, Co, CoZrMoNi or TbFe. As a detector they used a micro-bridge-DC-SQUID deposited onto or next to the sample. The sample and detector were patterned by electron-beam lithography. The dynamics and the temperature dependence of the magnetization reversal was studied in view of MQT.
26. Wernsdorfer W, Hasselbach K, Benoit A, Cernicchiaro G, Mailly D, Barbara B, Thomas L. Measurement of the dynamics of the magnetization reversal in individual single-domain Co particles. J Mag Mag Mat. 151:1995;38-44.
27. Wernsdorfer W, Doudin B, Mailly D, Hasselbach K, Benoit A, Meier J, Ansermet JP, Barbara B. Nucleation of the magnetization reversal in individual nanosized nickel wires. Phys Rev Lett. 77:1996;1873-1876.
28. Ledermann M, Schultz S, Ozaki M. Measurement of the dynamics of the magnetization reversal in individual single-domain ferromagnetic particles. Phys Rev Lett. 73:1994;1986-1989.
29. Awschalom DD, DiVincenzo DP. Complex dynamics of mesoscopic magnets. Phys Today. 48:1995;43-48.
30. Wernsdorfer W, Bonet Orozco E, Hasselbach K, Benoit A, Barbara B, Demoncy N, Loiseau A, Boivin D, Pascard H, Mailly D. Experimental evidence of the Néel-Brown model of magnetization reversal. Phys Rev Lett. 78:1997;1791-1794 The first magnetization measurements of individual ferromagnetic nanoparticles (15-30 nm) at very low temperatures (0.1-6 K) are presented. Waiting time, switching field and telegraph noise measurements showed for the first time that the magnetization reversal of a well prepared ferromagnetic nanoparticle can be described by thermal activation over a single-energy barrier as originally proposed by Néel and Brown. The activation volume estimated by these measurements was close to the particle volume.
31. Coppinger F, Genoe J, Maude DK, Genner U, Portal JC, Singer KE, Rutter P, Taskin T, Peaker AR, Wright AC. Single domain switching investigated using telegraph noise spectroscopy: possible evidence for macroscopic quantum tunneling. Phys Rev Lett. 75:1995;3513-3516 The authors studied telegraph noise (two-level fluctuations) in the magnetoresistance of Er-doped GaAs in order to probe the magnetic moment of small ErAs clusters formed during the molecular bean epitaxy growth process. At high temperatures the two-level fluctuations are thermally activated but below 350mK a saturation of the switching time is observed which was interpreted by MQT.
32. Hong K, Giordano N. New effects in ferromagnetic nanostructures. J Mag Mag Mat. 151:1995;396-402 The authors show the feasibility of studying domain wall motion by magnetoresistance measurements. They found that the domain walls were often pinned at structural defects, such as width fluctuations. It appears that at high temperatures the walls escaped from the pinning sites by thermal activation over the associated potential barrier. At temperatures lower than 5K, the authors observed deviations which they interpreted by MQT.
33. Hong K, Giordano N. Evidence for domain wall tunneling in a quasi-one dimensional ferromagnet. J Phys Condens Matter. 8:1996;L301-L309.
34. Hong K, Giordano N. Effect of microwaves on domain wall motion in thin Ni wires. Europhys Lett. 36:1996;147-152.
35. Stamp PCE. Quantum dynamics and tunneling of domain walls in ferromagnetic insulators. Phys Rev Lett. 66:1991;2802-2805.
36. Chudnovsky EM, Iglesias O, Stamp PCE. Quantum tunneling of domain walls in ferromagnet. Phys Rev B. 46:1992;5392-5404.
37. Tatara G, Fukuyama H. Macroscopic quantum tunneling of a domain wall in a ferromagnetic metal. Phys Rev Lett. 72:1994;772-775.
38. Gunther L, Barbara B. Quantum tunneling across a domain-wall junction. Phys Rev B. 49:1994;3926-3933.
39. Barbara B, Wegrowe JE, Sampaio LC, Noziéres JP, Uehara M, Novals M, Paulsen C, Tholence JL. Quantum tunneling in magnetic particles, layers and multilayers. Physica Scripta. T49:1993;268-273.
40. Wegrowe JE, Ballou R, Barbara B, Sulpice A, Amaral VS, Mailly D. Magnetic after effect experiments at low temperature: linear response and quantum noise. Phys Rev B. 52:1995;3466-3470.
41. Wegrowe JE, Barbara B, Amaral VS, Sousa JB. Unusual slow magnetic relaxation on a SmCo2/GdCo2 domain wall junction. J Mag Mag Mat. 161:1996;133-138.
42. Mangin S, Marchal G, Wernsdorfer W, Sulpice A, Mailly D, Barbara B. Static and dynamical study of the passage of a 180°domain wall over an artificial energy barrier. J Mag Mag Mat. 165:1997;13-16.
43. Garg A. Suppression of macroscopic quantum coherence in magnetic particles by nuclear spins. Phys Rev Lett. 74:1995;1458-1461.
44. Awschalom DD, Smyth JF, Grinstein G, Di Vincenzo DP, Loss D. Macroscopic quantum tunneling in magnetic proteins. Phys Rev Lett. 68:1992;3092-3095.
45. Gider S, Awschalom DD, Douglas T, Mann S, Chaparala M. Classical and quantum magnetic phenomena in natural and artificial ferritin proteins. Science. 268:1995;77-80 Artificial ferritin has been synthesized with control of the magnetic state and the particle size over an order of magnitude in the number of iron atoms. The magnetic properties were studied in a temperature range of 20mK-300K and in a field range of 10-9 T and 27 T in order to investigate the possibility of Macroscopic Quantum Coherence (MQC). They found a resonance frequency, which was dependent on the particle size, which may be due to MQC.
46. Gider G, Awschalom DD, Douglas T, Wong K, Mann S, Cain G. Classical and quantum magnetism in synthetic ferritin proteins. J Appl Phys. 79:1996;5324-5326.
47. Tejada J. Does macroscopic quantum coherence occur in ferritin? Science. 272:1996;424-424.
48. Garg A. Does Macroscopic Quantum Coherence occur in ferritin? Science. 272:1996;424-425.
49. Vernier N, Bellessa G. Nonlinear magnetic susceptibility in a Kramers-ion doped glass. Phys Rev Lett. 71:1993;4063-4066.
50. Rouse R, Han S, Lukens JE. Observation of resonant tunneling between macroscopically distinct quantum levels. Phys Rev Lett. 75:1995;1614-1617.
51. Friedman J, Sarachik MP, Tejada J, Maciejewski J, Ziolo R. Macroscopic measurements of resonant magnetization tunneling in high-spin molecules. Phys Rev Lett. 76:1996;3820-3833 The observation of steps at regular intervals of magnetic field in the hysteresis loop of a macroscopic sample of partially oriented manganese cluster crystallites are reported. Following the work in [10] and [55], the authors proposed that the observed effects were manifestations of thermally assisted, field-tuned resonant tunneling between quantum spin states.
52. Thomas L, Lionti F, Ballou R, Sessoli R, Gatteschi D, Barbara B. Macroscopic quantum tunneling of magnetization in a single crystal of nanomagnets. Nature. 383:1996;145-147 Magnetization experiments performed on a single crystal of Mn12-acetate clearly demonstrate the existence of thermally activated resonant tunneling of magnetization. The clear observation of quantized hysteresis loops, completed by magnetic relaxation experiments, showed that the relaxation rate increased by several orders of magnitude when the field was tuned to a step or when the temperature was increased.
53. Sessoli R, Gatteschi D, Caneschi A, Novak MA. Magnetic bistability in a metal-ion cluster. Nature. 365:1993;141-143.
54. Paulsen C, Park JG, Barbara B, Sessoli R, Caneschi A. Novel features in the relaxation times of Mn12-Ac. J Mat Mag Mat. 140-144:1995;379-380.
55. Novak MA, Sessoli R. AC susceptibility relaxation studies on a manganese organic cluster compound : Mn12-Ac. Gunther L, Barbara B. Quantum tunneling of magnetisation. 301:1995;171-188 Kluwer, Dordrecht. [NATO ASI Series E: Applied Sciences].
56. Burin AL, Prokofev NV, Stamp PCE. Comment on tunneling in mesoscopic magnetic molecules. Phys Rev Lett. 76:1996;3040-3041.