Autor: Okimoto, Y. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Search for the Photo-Induced Hidden Phase in Inorganic and Organic Systems
Autorzy:: Koshihara, S.
Onda, K.
Okimoto, Y.
Ishikawa, T.
Powiązania:: https://bibliotekanauki.pl/articles/1489970.pdf
Data publikacji:: 2012-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.47.J-
63.20.kd
71.30.+h
71.45.Lr
Opis:: We review the dynamical behavior of strongly electron-lattice (orbital) coupled system induced by photo-excitation of fs laser pulse. By virtue of the femtosecond (fs) spectroscopy and picosecond (ps) time-resolved X-ray diffraction measurements, we demonstrate that the photo-irradiation creates new ordered state so called as "hidden phase" which can never be realized under thermo-equilibrium condition. This exotic phase commonly plays the key role for realizing the gigantic photo-induced changes in optical properties of inorganic and organic electron-lattice strongly coupled systems.
Źródło:: Acta Physica Polonica A; 2012, 121, 2; 328-331
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Photoinduced Ionic to Neutral Phase Transition in TTF-CA Studied by Time-Resolved Infrared Vibrational Spectroscopy
Autorzy:: Matsubara, Y.
Yoshida, T.
Ishikawa, T.
Okimoto, Y.
Koshihara, S.
Onda, K.
Powiązania:: https://bibliotekanauki.pl/articles/1489994.pdf
Data publikacji:: 2012-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.30.Jw
78.47.D-
78.47.jg
Opis:: We studied the photoinduced ionic to neutral phase transition in tetrathiafulvalene-p-chloranil (TTF-CA) using time-resolved infrared vibrational spectroscopy. By monitoring the charge sensitive $b_{1u}$ $ν_{10}$ band of CA after photoexcitation by a 1.55 eV pulse, we found that the photoinduced N-phase has the same charge of the N-phase in thermal equilibrium and there is no charge variation during the photoinduced phase transition. We also found that the photoinduced N-phase grows through at least two steps over 300 ps.
Źródło:: Acta Physica Polonica A; 2012, 121, 2; 340-342
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 3.

Tytuł:: Ultrafast Dynamics of Photoinduced Electronic Phase Modulation in Ladder Cuprate of $Sr_{14 - x}Ca_{x}Cu_{24}O_{41}$
Autorzy:: Fukaya, R.
Kunitomo, M.
Okimoto, Y.
Ishikawa, T.
Onda, K.
Koshihara, S.
Yui, H.
Sasagawa, T.
Powiązania:: https://bibliotekanauki.pl/articles/1489955.pdf
Data publikacji:: 2012-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.47.-p
74.72.-h
78.20.-e
Opis:: Ultrafast carrier dynamics caused by photoexcitation in quasi-one-dimensional two-leg ladder cuprate $Sr_4Ca_{10}Cu_{24}O_{41}$ was investigated by the femtosecond reflection spectroscopy. After the photoexcitation along the leg direction, the transient reflectivity changes (Δ R/R) in the mid-infrared region showed instant decrease within 150 fs. The suppressed Δ R/R increased so rapidly on the picosecond time scale that the reflectivity value finally became larger than that in the initial state. Such a successive response in Δ R/R, which was also observed in other photon energy regions, is discussed in terms of ultrafast variation of the Drude weight in the ladder system by the photoirradiation.
Źródło:: Acta Physica Polonica A; 2012, 121, 2; 310-312
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 4.

Tytuł:: Femtosecond Reflection Spectroscopy in $La_{1.5}Sr_{0.5}CoO_4$
Autorzy:: Egawa, T.
Okimoto, Y.
Fukaya, R.
Onda, K.
Ishikawa, T.
Koshihara, S.
Isayama, A.
Sasagawa, T.
Powiązania:: https://bibliotekanauki.pl/articles/1489953.pdf
Data publikacji:: 2012-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.47.J-
78.47.jg
Opis:: Ultrafast optical response has been investigated using fs laser system on a perovskite-type cobalt oxide, $La_{1.5}Sr_{0.5}CoO_4$. After the photoirradiation at room temperature, the time profile of relative change of reflectance (Δ R/R) shows a sudden change within the pulse duration ( ≈ 150 fs) and decays with a lifetime of ≈ 330 fs. The sign of Δ R/R after the photoexcitation is positive in the mid-infrared region (at 0.50 eV) while negative in the visible energy region (at 2.0 eV), implying photoinduced change of the electronic structure after the photoexcitation.
Źródło:: Acta Physica Polonica A; 2012, 121, 2; 307-309
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 5.

Tytuł:: Slow Dynamics of the Photoinduced Phase Transition in $Pd(dmit)_2$ Salts (dmit = 1,3-dithiol-2-thione-4,5-dithiolate)
Autorzy:: Ishikawa, T.
Tanaka, T.
Fukazawa, N.
Matsubara, Y.
Okimoto, Y.
Onda, K.
Koshihara, S.
Tamura, M.
Kato, R.
Powiązania:: https://bibliotekanauki.pl/articles/1408855.pdf
Data publikacji:: 2012-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.40.Me
78.47.D-
78.47.jg
78.55.Kz
78.66.Qn
Opis:: Slow dynamics of the initially photoinduced state has been observed by the pump-probe type time-resolved reflection spectroscopy in the charge separated phase of the half-filled strong dimer system, $Et_2Me_2Sb[Pd(dmit)_2]_2$ (dmit = 1,3-dithiol-2-thione-4,5-dithiolate). We have succeeded to reproduce the probe photon energy dependence of the time profile qualitatively in the time delay range from 10 ps to 1 ns assuming the dynamical expansion of the domain of the photo-induced dimer-Mott insulating phase in the host charge-separated one.
Źródło:: Acta Physica Polonica A; 2012, 121, 2B; 316-318
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 6.

Tytuł:: Photoinduced Phase Transition in $Pr_{0.5}Ca_{0.5}CoO_3$ Studied by Sequential Pulse Excitations
Autorzy:: Seko, K.
Okimoto, Y.
Kurashima, M.
Fukaya, R.
Egawa, T.
Ishikawa, T.
Onda, K.
Koshihara, S.
Kyomen, T.
Itoh, M.
Powiązania:: https://bibliotekanauki.pl/articles/1490006.pdf
Data publikacji:: 2012-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.66.-w
78.47.jg
Opis:: A perovskite-type cobalt oxide, $Pr_{0.5}Ca_{0.5}CoO_3$ (PCCO), shows photoinduced phase transition. In this study, we successively irradiated two laser pulses with different intensities to PCCO and probed the transient change of the reflection at 2.0 eV. Assuming propagation of the two different photoinduced metallic states, we could reproduce the time profiles as well as the magnitude in the reflectance change, indicating the fabrication of the photoinduced multilayered thin film in $Pr_{0.5}Ca_{0.5}CoO_3$.
Źródło:: Acta Physica Polonica A; 2012, 121, 2; 369-371
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

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