activity
20052024
most citedProbing XY phase transitions in a Josephson junction array with tunable frustration

13 citations · 47 across the 8 of their papers we have counts for

collaborators

8 papers

cond-mat.other2024

Influence of Magnetic Field on Surface Andreev Bound States in Superfluid He-B Studied by Mobility of Electron Bubble

Hiroki Ikegami, Kimitoshi Kono, Yasumasa Tsutsumi

The B phase of superfluid He (He-B) is topologically nontrivial and the surface Andreev bound states formed on a surface are conceived as Majorana fermions.…

cond-mat.other2024

Contribution of Andreev reflection to the mobility of surface state electrons on superfluid He-B

Yasumasa Tsutsumi, Hiroki Ikegami, Kimitoshi Kono

The mobility of the Wigner solid on the superfluid He is determined by the momentum transfer from the scattered He quasiparticles at the free surface. The scattering proces…

cond-mat.supr-con2022★ 7 cited

Insulating Phase in Two-dimensional Josephson-Junction Arrays Investigated by Nonlinear Transport

Hiroki Ikegami, Yasunobu Nakamura

We present experimental investigations of transport properties in the insulating phase of two-dimensional Josephson-junction arrays (JJAs) by systematically changing the ratio of J…

quant-ph2020★ 13 cited

Probing XY phase transitions in a Josephson junction array with tunable frustration

R. Cosmic, K. Kawabata, Y. Ashida +5

The seminal theoretical works of Berezinskii, Kosterlitz, and Thouless presented a new paradigm for phase transitions in condensed matter that are driven by topological excitations…

cond-mat.other2018★ 13 cited

Review: Observation of Majorana Bound States at a Free Surface of He-B

Hiroki Ikegami, Kimitoshi Kono

The -wave superfluid He is a textbook example of topological superfluids. Among its multiple superfluid phases, the B phase (He-B) is known as a topological state protec…

quant-ph2018★ 10 cited

Circuit QED-based measurement of vortex lattice order in a Josephson junction array

R. Cosmic, Hiroki Ikegami, Zhirong Lin +3

Superconductivity provides a canonical example of a quantum phase of matter. When superconducting islands are connected by Josephson junctions in a lattice, the low temperature sta…