Ultrafast optical switching to a metallic state by photoinduced mott transition in a halogen-bridged nickel-chain compound.
We demonstrate the ultrafast photoinduced Mott transition from a charge transfer insulator to a metal in a halogen-bridged Ni-chain compound by pump-probe reflection spectroscopy. Upon the irradiation of a 130-femtosecond laser pulse, the spectral weight of the gap transition is transferred to the inner-gap region. When the photoexcitation density exceeds 0.1/Ni site, the Drude-like high-reflection band appears in the infrared region, signaling the formation of a metallic state. The photogeneration of the metallic state and the subsequent recovery to the original gapped state occur within a few picoseconds.
Iwai
S
S
Correlated Electron Research Center (CERC), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8564, Japan.
Ono
M
M
Maeda
A
A
Matsuzaki
H
H
Kishida
H
H
Okamoto
H
H
Tokura
Y
Y