CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
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Terahertz Emission of Ferromagnetic Ni-Fe Thin Films Excited by Ultrafast Laser Pulses
SHEN Jian** , ZHANG Huai-Wu, LI Yuan-Xun
State Key Laboratory of Electronic Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054
Terahertz Emission of Ferromagnetic Ni-Fe Thin Films Excited by Ultrafast Laser Pulses
SHEN Jian** , ZHANG Huai-Wu, LI Yuan-Xun
State Key Laboratory of Electronic Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054
Abstract ：It is believed that the ultrafast demagnetization process in ferromagnetic film is intrinsically a thermal effect, which is induced by ultrafast laser pulses. We present experimental evidence that such ultrafast demagnetization of the NiFe thin film can radiate electromagnetic waves in the terahertz range. We also demonstrate that the magnitude of the terahertz electromagnetic pulse emitted from ferromagnetic films after pulsed laser excitation can be tuned by the Gilbert damping factor α , which is conventionally used to describe damping of GHz precession motion of magnetization. Different damping factors are obtained by varying the normal metal film adjacent to the magnetic film via spin pumping. The measured radiated electric field in the far field is found to be proportional to the Gilbert damping factor.
收稿日期: 2012-03-13
出版日期: 2012-05-31
:
75.78.Jp
(Ultrafast magnetization dynamics and switching)
42.65.Re
(Ultrafast processes; optical pulse generation and pulse compression)
78.47.J-
(Ultrafast spectroscopy (<1 psec))
[1] Tehrani S, Slaughter J M, Chen E, Durlam M, Shi J and DeHerrera M 1999 IEEE Trans. Magn. 35 2814 2005 Phys. Rev. Lett. 95 267207 1996 Phys. Rev. Lett. 76 4250 1997 Phys. Rev. Lett. 78 4861 2000 Phys. Rev. Lett. 85 844 2009 Nature Phys. 5 515 2010 Rev. Mod. Phys. 82 2731 2003 Philos. Tran. R. Soc. London A 361 2827 2004 Appl. Phys. Lett. 84 3465 2004 J. Phys. Condens. Matter 16 R995 2006 J. Phys. Condens. Matter 18 R501 2006 Low. Temp. Phys. 32 748 1998 Phys. Rev. B 58 12134 2001 Phys. Rev. B 65 012413 1999 Phys. Rev. B 59 R6608 2000 Phys. Rev. B 61 16956 1995 Appl. Phys. Lett. 67 3523 1996 Appl. Phys. Lett. 69 2321 2002 Phys. Rev. B 66 104413 Microwave Engineering 3rd edn (New York: Wiley)
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2012, Vol. 29 
