Quantum Condensate Research Team

Principal Investigator

PI Name Masahito Ueda
Degree Ph.D.
Title Team Leader
Brief Resume
1988Researcher, NTT Basic Research Laboratories
1994Associate Professor, Hiroshima University
2000Professor, Tokyo Institute of Technology
2008Professor, University of Tokyo (-present)
2014Team Leader, Quantum Condensate Research Team, Quantum Information Electronics Division, RIKEN Center for Emergent Matter Science (-present)


We aim to explore physics frontiers at the that lie at the boarderlines between quantum physics, measurement, information and thermodynamics. In particular, we explore novel phenomena in ultracold atoms which offer a versatile tool to investigate universal quantum phenomena that are independent of material-specific parameters.

Research Fields

Physics, Engineering, Mathematics, Multidisciplinary


Ultracold atoms
Bose-Einstein condensates
Optical lattice
Quantum simulation
Quantum correlations


Topological excitations in Bose-Einstein condensates

Bose-Einstein condensates offer a cornucopia of symmetry breaking because a rich variety of internal degrees of freedom are available depending on the atomic species. We have used these degrees of freedom to explore various aspects of symmetry breaking and topological excitations. Among them are the so-called Kibble-Zurek mechanism in which the order parameter develops singularities after some parameter of the system is suddenly quenched. Ordinary vortices and spin vortices are found to emerge. We also investigate novel topological phenomena such as knot excitations in an antiferromagnetic Bose-Einstein condensate.

Ground-state phase diagram of a spin-2 Bose-Einstein condensate (BEC). Depending on the phase, different topological excitations appear.


Masahito Ueda

Team Leader masahito.ueda[at]riken.jp R

Naoto Tsuji

Research Scientist

Shun Uchino

Postdoctoral Researcher

Emi Yukawa

Postdoctoral Researcher

Junichi Iwasaki

Special Postdoctoral Researcher

Masaya Nakagawa

Special Postdoctoral Researcher



2-1 Hirosawa, Wako, Saitama 351-0198 Japan