Transition of Magnetoresistance in Co/Alq3 Granular Film on Silicon Substrate
SHU Qi2, ZHAO Xiao-Meng1,3, ZHANG Yan1,3, SHENG Peng1,3, TANG Zhen-Yao4, NI Gang 1,3
1Department of Optics Science and Engineering, Fudan University, Shanghai 2004332Laboratory of Advanced Materials, Fudan University, Shanghai 2004333The Key Lab for Advanced Photonic Materials and Devices, Fudan University, Shanghai 2004334Department of Material Science and Engineering, Fudan University, Shanghai 200433
Transition of Magnetoresistance in Co/Alq3 Granular Film on Silicon Substrate
SHU Qi2, ZHAO Xiao-Meng1,3, ZHANG Yan1,3, SHENG Peng1,3, TANG Zhen-Yao4, NI Gang 1,3
1Department of Optics Science and Engineering, Fudan University, Shanghai 2004332Laboratory of Advanced Materials, Fudan University, Shanghai 2004333The Key Lab for Advanced Photonic Materials and Devices, Fudan University, Shanghai 2004334Department of Material Science and Engineering, Fudan University, Shanghai 200433
摘要A Co0.38(Alq3)0.62 granular film is prepared using a co-evaporating technique on a silicon substrate with a native oxide layer. A crossover of magnetoresistance (MR) from positive to negative is observed. The positive MR ratio reaches 17.5% at room temperature (H=50 kOe), and the negative MR ratio reaches -1.35% at 15K (H=10 kOe). Furthermore, a metal-insulator transition is also observed. The transition of resistance and MR results from the channel switching of electron transport between the upper Co-Alq3 granular film and the inversion layer underneath. The negative MR originates from the tunneling magnetoresistance effect due to the tunneling conducting between adjacent Co granules, and the positive MR may be attributed to the transport of high mobility carriers in the SiO2/Si inversion layer.
Abstract：A Co0.38(Alq3)0.62 granular film is prepared using a co-evaporating technique on a silicon substrate with a native oxide layer. A crossover of magnetoresistance (MR) from positive to negative is observed. The positive MR ratio reaches 17.5% at room temperature (H=50 kOe), and the negative MR ratio reaches -1.35% at 15K (H=10 kOe). Furthermore, a metal-insulator transition is also observed. The transition of resistance and MR results from the channel switching of electron transport between the upper Co-Alq3 granular film and the inversion layer underneath. The negative MR originates from the tunneling magnetoresistance effect due to the tunneling conducting between adjacent Co granules, and the positive MR may be attributed to the transport of high mobility carriers in the SiO2/Si inversion layer.
SHU Qi;ZHAO Xiao-Meng;ZHANG Yan;SHENG Peng;TANG Zhen-Yao;NI Gang;. Transition of Magnetoresistance in Co/Alq3 Granular Film on Silicon Substrate[J]. 中国物理快报, 2009, 26(7): 77505-077505.
SHU Qi, ZHAO Xiao-Meng, ZHANG Yan, SHENG Peng, TANG Zhen-Yao, NI Gang,. Transition of Magnetoresistance in Co/Alq3 Granular Film on Silicon Substrate. Chin. Phys. Lett., 2009, 26(7): 77505-077505.
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