This paper investigates the transmission of terahertz pulse in the ultrathin film with terahertz time-domain spectroscopy and the terahertz pulse produced by the interaction between femtosecond laser pulse and Fe/Pt heterostructure. The thickness of the Fe/Pt film ranges from 2 nm to 8 nm. The terahertz wave exponentially decays in Fe and Pt ultrathin films, but it decays much faster in the bulk Fe and Pt. Due to the limitation in the thickness, electrons have much longer free path in the film plane, which increases the conductivity in the film plane. We also find that the laser pulse with 800 nm wavelength also decays faster in the ultrathin film.
HUANG Pan-hui
,
ZHANG Xiao-lei
,
LOU Shi-tao
. Thickness related THz-TDS of Fe/Pt heterostructure[J]. Journal of East China Normal University(Natural Science), 2017
, (3)
: 107
-113
.
DOI: 10.3969/j.issn.1000-5641.2017.03.012
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