(Ni79Fe21) 0.48-(Al2O3) 0.52 nano- granular film g

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(Ni79Fe21) 0.48-(Al2O3) 0.52 nano- granular film giant Hall effect

(79580A · mi) magnetic field H / (79580A · Ⅲ) granular film samples in Figure 4 the hysteresis loops and field Hall resistivity curve 5 . 『 · s} a ~ --. - 4.0 ----- a share - a --- Wei a - a 0o Figure 5 at room temperature (NiT9Fe21) 0.48-(AhOa) o, s2 granular films . And the curve in Figure 6 is (Ni79Fe21) o48 a (Al203) o52 granular film samples of the TEM photographs. Can be seen from the chart , nano- particles encapsulated in Ab in Ni79Fe21 , and even into the network structure with each other , near the percolation threshold, the electron transport is limited to a small width of the channel, is likely to lead e- Decoherence length than the channel width,[link widoczny dla zalogowanych], electrons can not look into particles , but the wave , the electron wave function of the question, there is interference, it is this quantum coherence effect may result in NiFe-A1203 granular film samples of the giant Hall Effect. By finely adjusting the volume fraction of metal , the metal particles to ask each other, connected , and the narrower the channel , electronic asked the stronger the effect of quantum coherence , Hall-effect sample the more significant . Figure 6 (Ni79Fe21) 0.48. (AI2o3) 0.52 granular film samples of the TEM photo 3 Conclusion magnetron sputtering using a series of different (Ni79Fe2 ~) r (AI203) content of the granular film at room temperature in (Ni7. Fe21) o48 a (A1203 ) o. Observed in 52 granular film samples to about 4.5n · cm of saturated Hall resistivity than pure Hall effect of ferromagnetic metals significantly increased. Annealing temperature to 300 ℃, (iFe21) o48 a (A1203) o52 granular films saturated Hall resistivity decreased only slightly , indicating that the granular films with good thermal stability. TEM images show effects of quantum coherence between the electrons significantly , which may lead to the Hall effect increases the main reason. Thank sample preparation and measurement is the Department of Physics , Nanjing University State Key Laboratory of Solid State Microstructures completed . In the course of the study , by the Nigang Bo Shi , the Dr. Wang Zhiming , Dr. Gao Jun of the support and help. In this deeply grateful.