TY - JOUR
T1 - Photon energy dependence of Kerr rotation in GeTe/Sb2Te3 chalcogenide superlattices
AU - Suzuki, Takara
AU - Mondal, Richarj
AU - Saito, Yuta
AU - Fons, Paul
AU - Kolobov, Alexander V.
AU - Tominaga, Junji
AU - Shigekawa, Hidemi
AU - Hase, Muneaki
PY - 2019/7/15
Y1 - 2019/7/15
N2 - We report on pump-probe based helicity dependent time-resolved Kerr measurements under infrared excitation of chalcogenide superlattices, consisting of alternately stacked GeTe and Sb2Te3 layers. The Kerr rotation signal consists of the specular inverse Faraday effect (SIFE) and the specular optical Kerr effect (SOKE), both of which are found to monotonically increase with decreasing photon energy over a sub-eV energy range. Although the dependence of the SIFE can be attributed to the response function of direct third-order nonlinear susceptibility, the magnitude of the SOKE reflects cascading second-order nonlinear susceptibility resulting from electronic transitions between bulk valence/conduction bands and interface-originating Dirac states of the superlattice.
AB - We report on pump-probe based helicity dependent time-resolved Kerr measurements under infrared excitation of chalcogenide superlattices, consisting of alternately stacked GeTe and Sb2Te3 layers. The Kerr rotation signal consists of the specular inverse Faraday effect (SIFE) and the specular optical Kerr effect (SOKE), both of which are found to monotonically increase with decreasing photon energy over a sub-eV energy range. Although the dependence of the SIFE can be attributed to the response function of direct third-order nonlinear susceptibility, the magnitude of the SOKE reflects cascading second-order nonlinear susceptibility resulting from electronic transitions between bulk valence/conduction bands and interface-originating Dirac states of the superlattice.
KW - chalcogenide superlattices
KW - inverse Faraday effect
KW - Optical Kerr effect
KW - ultrafast spectroscopy
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U2 - 10.1088/1361-648X/ab2e9f
DO - 10.1088/1361-648X/ab2e9f
M3 - Article
C2 - 31265998
AN - SCOPUS:85071070035
VL - 31
JO - Journal of Physics Condensed Matter
JF - Journal of Physics Condensed Matter
SN - 0953-8984
IS - 41
M1 - 415502
ER -