22 citations · 131 across the 10 of their papers we have counts for
10 papers
Imaging based feedback cooling of a levitated nanoparticle
Yosuke Minowa, Keisuke Kato, Shoki Ueno +4
Imaging-based detection of the motion of the levitated nanoparticles complements a widely-used interferometric detection method, providing a precise and robust way to estimate the…
Visualisation of quantised vortex reconnection as enabled by laser ablation
Yosuke Minowa, Shota Aoyagi, Sosuke Inui +4
Impurity injection into superfluid helium is a simple yet unique method with diverse applications, including high-precision spectroscopy, quantum computing, nano/micro materialsynt…
Optical trapping of nanoparticles in superfluid helium
Yosuke Minowa, Xi Geng, Keisuke Kokado +4
Optical tweezers, the three-dimensional confinement of a nanoparticle by a strongly focused beam of light, have been widely employed in investigating biomaterial nanomechanics, nan…
Excitation efficiency and limitations of the luminescence of Eu3+ ions in GaN
Dolf Timmerman, Brandon Mitchell, Shuhei Ichikawa +3
The excitation efficiency and external luminescence quantum efficiency of trivalent Eu3+ ions doped into gallium nitride (GaN) was studied under optical and electrical excitation.…
Inner structure of ZnO microspheres fabricated via laser ablation in superfluid helium
Yosuke Minowa, Yuya Oguni, Masaaki Ashida
ZnO microspheres fabricated via laser ablation in superfluid helium were found to have bubble-like voids. Even a microsphere demonstrating clear whispering gallery mode resonances…
In-situ tuning of whispering gallery modes of levitated silica microspheres
Yosuke Minowa, Yusuke Toyota, Masaaki Ashida
We demonstrated the tuning of whispering gallery modes (WGMs) of a silica microsphere during optical levitation through the annealing process. We determined the annealing temperatu…
Effects of Anisotropy and Local Crystal Structure on Superconductivity in (=BaSr, SrCa and Eu)
Toru Adachi, Yusuke Nakamatsu, Tatsuya Kobayashi +8
We investigated the effects of anisotropy and local crystal structure on superconductivity (SC) in As/P solid solution systems, $A\mathrm{Fe_{2}}(\mathrm{As}_{1-x}\mathrm{P}_…
Ultrafast near infrared photoinduced absorption in a multiferroic single crystal of bismuth ferrite
Eiichi Matsubara, Takeshi Mochizuki, Masaya Nagai +2
We studied the ultrafast third-order optical nonlinearity in a single crystal of multiferroic bismuth ferrite (BiFeO3) in the near-infrared range of 0.5-1.0 eV, where the material…
Optical levitation of microdroplet containing a single quantum dot
Yosuke Minowa, Ryoichi Kawai, Masaaki Ashida
We demonstrate the optical levitation or trapping in helium gas of a single quantum dot (QD) within a liquid droplet. Bright single photon emission from the levitated QD in the dro…
Dimensionality dependence of optical nonlinearity and relaxation dynamics in cuprates
M. Ashida, Y. Taguchi, Y. Tokura +4
Femtosecond pump-probe measurements find pronounced dimensionality dependence of the optical nonlinearity in cuprates. Although the coherent two-photon absorption (TPA) and linear…