National Institute Of Technology, Ishikawa College

output

20022021

most citedVortices in multicomponent Bose-Einstein condensates

245 citations

researchers with a paper here

Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.

collaborating institutions

16 papers

quant-ph2021

Odd-periodic Grover walk

Yusuke Yoshie

The Grover walk is one of the most well-studied quantum walks on graphs. In this paper, we investigate its periodicity to reveal the relationship between the quantum walk and the u…

math.GT2016★ 5 cited

Non-holomorphic Lefschetz fibrations with $(- 1)$ -sections

Noriyuki Hamada, Ryoma Kobayashi, Naoyuki Monden

We construct two types of non-holomorphic Lefschetz fibrations over $S^{2}$ with $(- 1)$ -sections ---hence, they are fiber sum indecomposable--- by giving the corresponding positive r…

cond-mat.mes-hall2016★ 33 cited

Longitudinal spin-relaxation of donor-bound electrons in direct bandgap semiconductors

Todd Karin, Xiayu Linpeng, M. V. Durnev +6

We measure the donor-bound electron longitudinal spin-relaxation time ( $T_{1}$ ) as a function of magnetic field ( $B$ ) in three high-purity direct-bandgap semiconductors: GaAs, InP, a…

math.GT2016

A normal generating set for the Torelli group of a compact non-orientable surface

Ryoma Kobayashi

For a compact surface $S$ , let $I (S)$ denote the Torelli group of $S$ . For a compact orientable surface $Σ$ , $I (Σ)$ is generated by BSCC maps and BP maps. For a…

math.GT2015

A finite generating set for the level 2 twist subgroup of the mapping class group of a closed non-orientable surface

Ryoma Kobayashi, Genki Omori

We obtain a finite generating set for the level 2 twist subgroup of the mapping class group of a closed non-orientable surface. The generating set consists of crosscap pushing maps…

math.GT2014★ 3 cited

A normal generating set for the Torelli group of a non-orientable closed surface

Susumu Hirose, Ryoma Kobayashi

For a closed surface $S$ , its Torelli group $I (S)$ is the subgroup of the mapping class group of $S$ consisting of elements acting trivially on $H_{1} (S; Z)$ . When…

gr-qc2014★ 7 cited

Membranes with a symmetry of cohomogeneity one

Hiroshi Kozaki, Tatsuhiko Koike, Hideki Ishihara

We study the dynamics of the Nambu-Goto membranes with cohomogeneity one symmetry, i.e., the membranes whose trajectories are foliated by homogeneous surfaces. It is shown that the…

math.GT2014★ 4 cited

Lefschetz pencils and finitely presented groups

Ryoma Kobayashi, Naoyuki Monden

In this paper, given a finitely presented group $Γ$ , we provide the explicit monodromy of a Lefschetz fibration with $(- 1)$ -sections whose total space has fundamental group $Γ$ by…

gr-qc2009★ 15 cited

Exactly solvable strings in Minkowski spacetime

Hiroshi Kozaki, Tatsuhiko Koike, Hideki Ishihara

We study the integrability of the equations of motion for the Nambu-Goto strings with a cohomogeneity-one symmetry in Minkowski spacetime. A cohomogeneity-one string has a world su…

gr-qc2008★ 6 cited

Perturbations of Spacetime around a Stationary Rotating Cosmic String

Kouji Ogawa, Hideki Ishihara, Hiroshi Kozaki +1

We consider the metric perturbations around a stationary rotating Nambu-Goto string in Minkowski spacetime. By solving the linearized Einstein equations, we study the effects of az…

cond-mat.other2006★ 45 cited

Dynamical vortex phases in a Bose-Einstein condensate driven by a rotating optical lattice

Kenichi Kasamatsu, Makoto Tsubota

We present simulation results of the vortex dynamics in a trapped Bose-Einstein condensate in the presence of a rotating optical lattice. Changing the potential amplitude and the r…

cond-mat.other2006★ 112 cited

Modulation instability and solitary wave formation in two-component Bose-Einstein condensates

Kenichi Kasamatsu, Makoto Tsubota

We investigate nonlinear dynamics induced by the modulation instability of a two-component mixture in an atomic Bose-Einstein condensate. The nonlinear dynamics is examined using n…

cond-mat.other2005★ 245 cited

Vortices in multicomponent Bose-Einstein condensates

Kenichi Kasamatsu, Makoto Tsubota, Masahito Ueda

We review the topic of quantized vortices in multicomponent Bose-Einstein condensates of dilute atomic gases, with an emphasis on that in two-component condensates. First, we revie…

cond-mat.other2005★ 41 cited

Three-dimensional dynamics of vortex lattice formation in Bose-Einstein condensates

Kenichi Kasamatsu, Masahiko Machida, Narimasa Sasa +1

We numerically study the dynamics of vortex lattice formation in a rotating cigar-shaped Bose-Einstein condensate. The study is a three-dimensional simulation of the Gross-Pitaevsk…

cond-mat.mes-hall2004★ 153 cited

Spin textures in rotating two-component Bose-Einstein condensates