97 citations · 477 across the 24 of their papers we have counts for
5 papers · 1 filter
First-Principles Study for the Anisotropy of Iron-based Superconductors toward Power and Device Applications
Hiroki Nakamura, Masahiko Machida, Tomio Koyama +1
Performing the first-principles calculations, we investigate the anisotropy in the superconducting state of iron-based superconductors to gain an insight into their potential appli…
Reply to the comment [arXiv:0903.5110] on "Mechanism of Terahertz Electromagnetic Emission from Intrinsic Josephson Junctions" [arXiv:0810.5268]
Masashi Tachiki, Tomio Koyama, Shouta Fukuya
We reply to the comment [arXiv:0903.5110] on our paper "Mechanism of Terahertz Electromagnetic Emission from Intrinsic Josephson Junctions" [arXiv:0810.5268].
Theory of vortex structure in Josephson junctions with multiple tunneling channels: Vortex enlargement as a probe of -wave superconductivity
Yukihiro Ota, Masahiko Machida, Tomio Koyama +1
We theoretically study Josephson vortex structures in Josephson junctions which have multiple tunneling channels caused by multiple superconducting gaps. Deriving "coupled sine-Gor…
Intergrain Josephson Currents in Multigap Superconductors: Microscopic Origin of Low Intergrain Critical Current and Its Recovery Potential in Iron-Pnictide Materials
Yukihiro Ota, Masahiko Machida, Tomio Koyama
We microscopically examine the intergrain Josephson current in iron-pnictide superconductors in order to solve the puzzle of why the intergrain current is much lower than the intra…
Theory of heterotic SIS Josephson junctions between single- and multi-gap superconductors
Yukihiro Ota, Masahiko Machida, Tomio Koyama +1
Using the functional integral method, we construct a theory of heterotic SIS Josephson junctions between single- and two-gap superconductors. The theory predicts the presence of in…