Takahiko Sasaki

Ray-wave correspondence in limacon-shaped semiconductor microcavities (2009)

Shinohara, Susumu, Hentschel, Martina, Wiersig, Jan, Sasaki, Takahiko, Harayama, Takahisa

The limacon-shaped semiconductor microcavity is a ray-chaotic cavity sustaining low-loss modes with mostly unidirectional emission patterns. Investigating these modes systematically, we show that the...

Metallic Pattern Fabrication in Organic Mott Insulating Crystal by Local X-Ray Irradiation (2008)

Yoneyama, Naoki, Sasaki, Takahiko, Kobayashi, Norio, Ikemoto, Yuka, Moriwaki, Taro, Kimura, Hiroaki

We have fabricated a metallic structure in an organic Mott insulator $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Cl. The periodic metallic domains of approximately 90$\times$90 $\mu$m$^2$ obtained by X-ray...

Impurity Effect on Superconducting Properties in Molecular Substituted Organic Superconductor $\kappa$-(ET)$_2$Cu(NCS)$_2$ (2007)

Yoneyama, Naoki, Sasaki, Takahiko, Oizumi, Hajime, Kobayashi, Norio

We report an impurity effect in the organic superconductor $\kappa$-(ET)$_2$Cu(NCS)$_2$ by substitution of the ET molecule with an analogue, bis(methyleneditio)tetrathiafulvalene (MT). The...

Dissipation in the superconducting state of kappa-(BEDT-TTF)2Cu(NCS)2 (2006)

Yin, Liang, Nam, Moon-Sun, Analytis, James G., Blundell, Stephen J., Ardavan, Arzhang, Schlueter, John A., ...

We have studied the interlayer resistivity of the prototypical quasi-two-dimensional organic superconductor $\kappa$-(BEDT-TTF)$_2$Cu(NCS)$_2$ as a function of temperature, current and magnetic...

High-field Magnetic Torque Measurements in (CH$_3$)$_2$CHNH$_3$CuCl$_3$ (2005)

Saito, Takehiro, Sasaki, Takahiko, Suzuki, Takao, Oosawa, Akira, Goto, Takayuki, Awaji, Satoshi, ...

High-field magnetic torque measurements were carried out in the spin gap system (CH$_3$)$_2$CHNH$_3$CuCl$_3$. It was observed that the magnitude of the magnetic torque $\tau$ is almost zero until the...

Superconducting Properties under Magnetic Field in Na$_{0.35}$CoO$_{2}{\cdot}1.3$H$_{2}$O Single Crystal (2004)

Sasaki, Takahiko, Badica, Petre, Yoneyama, Naoki, Yamada, Kazuyoshi, Togano, Kazumasa, Kobayashi, Norio

We report the in-plane resistivity and magnetic susceptibility of the layered cobalt oxide Na$_{0.35}$CoO$_{2}{\cdot}1.3$H$_{2}$O single crystal. The temperature dependence of the resistivity shows...

Substitution Effect by Deuterated Donors on Superconductivity in $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Br (2004)

Yoneyama, Naoki, Sasaki, Takahiko, Kobayashi, Norio

We investigate the superconductivity in the deuterated BEDT-TTF molecular substitution system $\kappa$-[(h8-BEDT-TTF)$_{1-x}$(d8-BEDT-TTF)$_x$]$_2$Cu[N(CN)$_2$]Br, where h8 and d8 denote fully...

Properties of Ferromagnetic Ga1-xMnxN Films Grown by Ammonia-MBE (2002)

Sonoda, Saki, Hori, Hidenobu, Yamamoto, Yoshiyuki, Sasaki, Takahiko, Sato, Masugu, Shimizu, Saburo, ...

Using ammonia as nitrogen source for molecular beam epitaxy, the GaN-based diluted magnetic semiconductor Ga1-xMnxN is successfully grown with Mn concentration up to x~6.8% and with p-type...

Superconducting Gap Structure of kappa-(BEDT-TTF)2Cu(NCS)2 Probed by Thermal Conductivity Tensor (2001)

Izawa, Koichi, Yamaguchi, Hidemasa, Sasaki, Takahiko, Matsuda, Yuji

The thermal conductivity of organic superconductor kappa-(BEDT-TTF)2Cu(NCS)2 (Tc =10.4 K) has been studied in a magnetic field rotating within the 2D superconducting planes with high alignment...