Yoshihiko Kanemitsu

a (2009)

Kazunari Matsuda, Tadashi Inoue, Yoichi Murakami, Shigeo Maruyama, Yoshihiko Kanemitsu

recombinations and exciton fine structures studied by

Photocarrier recombination dynamics in highly excited SrTiO3 studied by transient absorption and photoluminescence spectroscopy (2009)

Yamada, Yasuhiro, Yasuda, Hideki, Tayagaki, Takeshi, Kanemitsu, Yoshihiko

We studied photocarrier recombination processes in highly excited SrTiO3 crystals using pump-probe transient absorption (TA) and photoluminescence (PL) spectroscopy at room temperature. TA signals of...

Symmetry-induced nonequilibrium distributions of bright and dark exciton states in single carbon nanotubes (2009)

Matsunaga, Ryusuke, Miyauchi, Yuhei, Matsuda, Kazunari, Kanemitsu, Yoshihiko

We investigated the magnetic and temperature dependence of the bright and dark exciton luminescence spectra in single carbon nanotubes. We found that the phonon-induced exciton scattering rate from...

Radiative lifetimes and coherence lengths of one-dimensional excitons in single-walled carbon nanotubes (2009)

Miyauchi, Yuhei, Hirori, Hideki, Matsuda, Kazunari, Kanemitsu, Yoshihiko

We evaluated the radiative lifetimes and the one-dimensional exciton coherence lengths in single-walled carbon nanotubes (SWNTs). The radiative lifetimes determined from simultaneous measurements of...

Composition dependent dynamics of biexciton localization in AlxGa1-xN mixed crystals (2009)

Hirano, Daisuke, Tayagaki, Takeshi, Yamada, Yoichi, Kanemitsu, Yoshihiko

We report the localization-dependent dynamics of biexcitons in AlxGa1−xN mixed crystals under exciton resonant excitation at low temperatures. After intense laser excitation, biexcitons rapidly...

Femtosecond Excitation Correlation Spectroscopy of Single-Walled Carbon Nanotubes : Analysis Based on Nonradiative Multiexciton Recombination Processes (2009)

Miyauchi, Yuhei, Matsuda, Kazunari, Kanemitsu, Yoshihiko

We studied the nonlinear time-resolved luminescence signals due to multiexciton recombination processes in single-walled carbon nanotubes (SWNTs) using femtosecond excitation correlation (FEC)...

Temperature dependence of photoluminescence spectra of undoped and electron-doped SrTiO3: Crossover from Auger recombination to single-carrier trapping (2009)

Yamada, Yasuhiro, Yasuda, Hideki, Tayagaki, Takeshi, Kanemitsu, Yoshihiko

We report unusual photoluminescence (PL) behaviors in highly photoexcited SrTiO3 crystals at low temperatures. The PL spectrum and dynamics show abrupt changes below 150 K in both nondoped and...

Mn-Mn couplings in Mn-doped CdS nanocrystals studied by magnetic circular dichroism spectroscopy (2009)

Taguchi, Seiji, Ishizumi, Atsushi, Tayagaki, Takeshi, Kanemitsu, Yoshihiko

We report on the optical and magnetic properties of Mn-doped CdS nanocrystals coated with a ZnS shell layer (CdS:Mn/ZnS core-shell nanocrystals) by magnetic circular dichroism (MCD) spectroscopy. The...

Mechanism of exciton dephasing in a single carbon nanotube studied by photoluminescence spectroscopy (2009)

Yoshikawa, Kohei, Matsunaga, Ryusuke, Matsuda, Kazunari, Kanemitsu, Yoshihiko

We studied the temperature and chirality dependence of the photoluminescence (PL) linewidth of single carbon nanotubes to clarify the mechanism of exciton dephasing. The PL linewidth of a single...

Photoluminescence dynamics and reduced Auger recombination in Si1-xGex/Si superlattices under high-density photoexcitation (2009)

Tayagaki, Takeshi, Fukatsu, Susumu, Kanemitsu, Yoshihiko

Optical gain and stimulated emission processes in Si nanostructures are controlled by the dynamics of high-density carriers. Here, we report photoluminescence (PL) dynamics and multiexciton...

Spatial distribution of carriers in SrTiO3 revealed by photoluminescence dynamics measurements (2008)

Yasuda, Hideki, Yamada, Yasuhiro, Tayagaki, Takeshi, Kanemitsu, Yoshihiko

We report on the optical determination of the carrier-density profiles near surfaces in SrTiO3 crystals by means of photoluminescence (PL) dynamics measurements. The PL dynamics under band-to-band...

Energy transfer in mixed CdSe and Au nanoparticle monolayers studied by simultaneous photoluminescence and Raman spectral measurements (2008)

Kawai, Masaki, Yamamoto, Aishi, Matsuura, Norihiro, Kanemitsu, Yoshihiko

We report photoluminescence (PL) and Raman-scattering (RS) spectra in close-packed CdSe/Au mixed nanoparticle (NP) monolayers as a function of the ratio of CdSe to Au NPs in the film. The RS...

Exciton energy transfer between the inner and outer tubes in double-walled carbon nanotubes (2008)

Hirori, Hideki, Matsuda, Kazunari, Kanemitsu, Yoshihiko

We have studied photoluminescence (PL) spectrum and dynamics of the inner nanotubes in double-walled carbon nanotubes (DWNTs) and compared PL properties between DWNTs and single-walled carbon...

Carrier multiplication in carbon nanotubes studied by femtosecond pump-probe spectroscopy (2008)

Ueda, Akihiro, Matsuda, Kazunari, Tayagaki, Takeshi, Kanemitsu, Yoshihiko

Carbon nanotubes are one of the excellent materials for studying the many-body effects of excitons because of their unique band structures and large exciton binding energies. We studied exciton...

Exciton fine structure in a single carbon nanotube revealed through spectral diffusion (2008)

Matsuda, Kazunari, Inoue, Tadashi, Murakami, Yoichi, Maruyama, Shigeo, Kanemitsu, Yoshihiko

We studied the spectral diffusion land exciton fine structures of single-walled carbon nanotubes (SWNTs) by using single carbon nanotube spectroscopy. Two types of single nanotube photoluminescence...

Direct and stepwise energy transfer from excitons to plasmons in close-packed metal and semiconductor nanoparticle monolayer films (2008)

Hosoki, Koshin, Tayagaki, Takeshi, Yamamoto, Shinpei, Matsuda, Kazunari, Kanemitsu, Yoshihiko

We studied the dynamics of photoluminescence (PL) and energy transfer in close-packed monolayer films of CdSe and Au nanoparticles (NPs) assembled using the Langmuir-Blodgett technique. The PL...

Dynamics of nonlinear blue photoluminescence and Auger recombination in SrTiO3 (2008)

Yasuda, Hideki, Kanemitsu, Yoshihiko

We report that the blue photoluminescence (PL) dynamics are dependent on both the photogenerated and the chemically doped carrier densities in SrTiO3. We found that the PL decay dynamics are well...

Dynamics of biexciton localization in AlxGa1-xN mixed crystals under exciton resonant excitation (2008)

Hirano, Daisuke, Tayagaki, Takeshi, Yamada, Yoichi, Kanemitsu, Yoshihiko

We report the localization dynamics of biexcitons in AlxGa1−xN mixed crystals under exciton resonant excitation at low temperatures. During a few tens of picoseconds just after intense laser...

Exciton fine structure in a single carbon nanotube revealed through spectral diffusion (2008)

Matsuda, Kazunari, Inoue, Tadashi, Murakami, Yoichi, Maruyama, Shigeo, Kanemitsu, Yoshihiko

We studied the spectral diffusion and exciton fine structures of single-walled carbon nanotubes (SWNTs) by using single carbon nanotube spectroscopy. Two types of single nanotube photoluminescence...

Photoluminescence enhancement and quenching of single CdSe/ZnS nanocrystals on metal surfaces dominated by plasmon resonant energy transfer (2008)

Matsuda, Kazunari, Ito, Yuichi, Kanemitsu, Yoshihiko

We studied the mechanism of the photoluminescence (PL) enhancement and quenching of single CdSe/ZnS nanocrystals on rough Au surfaces. Single nanocrystal spectroscopy revealed that the PL enhancement...

Energy transfer from semiconductor nanocrystal monolayers to metal surfaces revealed by time-resolved photoluminescence spectroscopy (2008)

Ueda, Akihiro, Tayagaki, Takeshi, Kanemitsu, Yoshihiko

We studied photoluminescence (PL) and energy transfer dynamics in CdSe nanocrystal (NC) assembled monolayers on Au surfaces. The close-packed CdSe NC monolayers were fabricated using the...

Exciton dephasing and multiexciton recombinations in a single carbon nanotube (2008)

Kazunari Matsuda, Tadashi Inoue, Yoichi Murakami, Shigeo Maruyama, Yoshihiko Kanemitsu

We studied the temperature and excitation intensity dependence of exciton luminescence in individual single-walled carbon nanotubes (SWNTs) using single nanotube photoluminescence (PL) spectroscopy....

Disorder-induced rapid localization of electron-hole plasmas in highly excited InxGa1-xN mixed crystals (2008)

Hirano, Daisuke, Tayagaki, Takeshi, Kanemitsu, Yoshihiko

In mixed semiconductor crystals, random potential fluctuations cause localized band-tail states below the band edge and control the optical spectrum and dynamics. We report the influence of these...

Exciton dephasing and multiexciton recombinations in a single carbon nanotube (2008)

Matsuda, Kazunari, Inoue, Tadashi, Murakami, Yoichi, Maruyama, Shigeo, Kanemitsu, Yoshihiko

We studied the temperature and excitation intensity dependence of exciton luminescence in individual single-walled carbon nanotubes (SWNTs) using single nanotube photoluminescence (PL) spectroscopy....

Exciton dephasing and multiexciton recombinations in a single carbon nanotube (2008)

Matsuda, Kazunari, Inoue, Tadashi, Murakami, Yoichi, Maruyama, Shigeo, Kanemitsu, Yoshihiko

We studied the temperature and excitation intensity dependence of exciton luminescence in individual single-walled carbon nanotubes (SWNTs) using single nanotube photoluminescence (PL) spectroscopy....

Mechanism of photoluminescence enhancement in single semiconductor nanocrystals on metal surfaces (2007)

Ito, Yuichi, Matsuda, Kazunari, Kanemitsu, Yoshihiko

We have studied the mechanism of the photoluminescence (PL) enhancement and quenching of single CdSe/ZnS core/shell nanocrystals on Au surfaces by means of single nanocrystal spectroscopy. The on-off...

Exciton localization of single-walled carbon nanotubes revealed by femtosecond excitation correlation spectroscopy (2006)

Hirori, Hideki, Matsuda, Kazunari, Miyauchi, Yuhei, Maruyama, Shigeo, Kanemitsu, Yoshihiko

Photoluminescence (PL) dynamics in single-walled carbon nanotubes (SWNTs) has been studied by the femtosecond excitation correlation method with a 150 fs time resolution. The SWNT samples were...

Exciton localization of single-walled carbon nanotubes revealed by femtosecond excitation correlation spectroscopy (2006)

Hirori, Hideki, Matsuda, Kazunari, Miyauchi, Yuhei, Maruyama, Shigeo, Kanemitsu, Yoshihiko

Photoluminescence (PL) dynamics in single-walled carbon nanotubes (SWNTs) has been studied by the femtosecond excitation correlation method with a 150 fs time resolution. The SWNT samples were...

Diameter dependence of exciton-phonon interaction in individual single-walled carbon nanotubes studied by microphotoluminescence spectroscopy (2006)

Inoue, Tadashi, Matsuda, Kazunari, Murakami, Yoichi, Maruyama, Shigeo, Kanemitsu, Yoshihiko

We have investigated the diameter dependence of the exciton luminescence linewidth in individual single-walled carbon nanotubes (SWNTs) by means of microphotoluminescence (µ-PL) spectroscopy. The...

Temperature dependence of exciton localization dynamics in InxGa1-xN epitaxial films (2006)

Kanemitsu, Yoshihiko, Tomita, Koichi, Hirano, Daisuke, Inouye, Hideyuki

We have studied the temperature dependence of exciton localization dynamics in InxGa1–xN epitaxial films (x=0.09) by means of optical Kerr-gate time-resolved photoluminescence (PL) spectral...

correlation spectroscopy: exciton localization (2006)

Hideki Hirori, Kazunari Matsuda, Yuhei Miyauchi, Shigeo Maruyama, Yoshihiko Kanemitsu

dynamics of single-walled carbon nanotubes revealed by femtosecond excitation

Subpicosecond luminescence spectroscopy of exciton localization in InxGa1-xN films (2005)

Kanemitsu, Yoshihiko, Tomita, Koichi, Inouye, Hideyuki

We have studied the exciton localization dynamics in InxGa1–xN epitaxial films with different In compositions (x=0.02, 0.05, and 0.09) by means of optical Kerr-gate time-resolved photoluminescence...

Photoluminescence properties of single Mn-doped CdS nanocrystals studied by scanning near-field optical microscopy (2005)

Ishizumi, Atsushi, Matsuda, Kazunari, Saiki, Toshiharu, White, C. W., Kanemitsu, Yoshihiko

We have fabricated Mn-doped CdS (CdS:Mn) nanocrystals embedded in Al2O3 matrices by sequential ion implantation and studied their photoluminescence (PL) properties by a scanning near-field optical...

Structural and luminescence properties of Eu-doped ZnO nanorods fabricated by a microemulsion method. Structural and luminescence properties of Eu-doped ZnO nanorods fabricated by a microemulsion method (2005)

Ishizumi, Atsushi, Kanemitsu, Yoshihiko

We have studied photoluminescence (PL) properties of Eu-doped ZnO (ZnO:Eu) nanorods fabricated by a microemulsion method. The ZnO:Eu nanorods have a hexagonal crystal structure and exhibit a sharp...

Photoluminescence dynamics of GaN under intense band-to-band and exciton resonant excitation (2005)

Nagai, Takehiko, Yamamoto, Aishi, Kanemitsu, Yoshihiko

We have studied the dynamics of highly dense exciton and electron-hole (e-h) systems in GaN by means of optical Kerr-gate time-resolved photoluminescence (PL) spectral measurements. In high-density...

Photoluminescence intermittency in an individual single-walled carbon nanotube at room temperature (2005)

Matsuda, K., Kanemitsu, Yoshihiko, Irie, K., Saiki, T., Someya, T., Miyauchi, Y., ...

We described the photoluminescence (PL) properties of individual micelle-encapsulated single-walled carbon nanotubes (SWNTs) at room temperature. Single PL peak from isolated individual SWNT with a...

Enhanced luminescence from electron-hole droplets in silicon nanolayers (2004)

Nihonyanagi, Satoshi, Kanemitsu, Yoshihiko

We have studied photoluminescence (PL) from the condensed phase in silicon-on-insulator samples with different Si layer thickness from 50 to 340 nm. Two major PL bands are observed at low...

Intersubband electronic Raman scattering in narrow GaAs single quantum wells dominated by single-particle excitations (2004)

Unuma, Takeya, Kobayashi, Kensuke, Yamamoto, Aishi, Yoshita, Masahiro, Hashimoto, Yoshiaki, Katsumoto, Shingo, ...

We measured resonant Raman scattering by intersubband electronic excitations in GaAs/AlAs single quantum wells (QWs) with well widths ranging from 8.5 to 18 nm. In narrow (less than 10 nm) QWs with...

Space-resolved photoluminescence of ZnS:Cu,Al nanocrystals fabricated by sequential ion implantation (2004)

Ishizumi, Atsushi, White, C. W., Kanemitsu, Yoshihiko

We report on photoluminescence (PL) properties of Cu- and Al-doped ZnS nanocrystals fabricated by sequential implantation of Zn+, S+, Cu+, and Al+ ions into Al2O3 matrices. The spatially resolved PL...

Band-gap renormalization in highly excited GaN (2004)

Nagai, Takehiko, Inagaki, Takeshi J., Kanemitsu, Yoshihiko

We have studied the band-gap renormalization in highly excited GaN thin films by means of photoluminescence (PL) spectral measurements from 6 to 300 K. The renormalized band-gap energy is determined...

Electric-Field Dependence of the Hole Drift Mobility in Molecularly Doped Polymers: Importance of the Disorder of Hopping Sites. (1998)

Kanemitsu, Yoshihiko, Funada, Hiroshi, Masumoto, Yasuaki

Time-of-flight (TOF) photoconductivity measurements were used to study the electric-field dependence of the drift mobility of holes in a polymer matrix doped with various molecules. It was found that...

Photoluminescent spectrum and dynamics of Si+-ion-implanted and thermally annealed SiO2 glasses (1996)

Kanemitsu, Yoshihiko, Shimizu, Naoya, Komoda, Takuya, Hemment, P. L. F., Sealy, Brian J.

We have experimentally studied the photoluminescent (PL) properties of Si clusters in fused silica matrices. Si clusters in the SiO2 matrices were fabricated by Si+-ion implantation (200 keV, 2 x...