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)

Outline

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

Keywords

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

Results

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.

Members

Masahito Ueda

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

Takashi Mori

Research Scientist

Lennart Justin Dabelow

Postdoctoral Researcher

Naoto Tsuji

Visiting Scientist

Publications

  1. E. Yukawa, and M. Ueda

    Morphological Superfluid in a Nonmagnetic Spin-2 Bose-Einstein Condensate

    Phys. Rev. Lett. 124, 105301 (2020)
  2. N. Kura, and M. Ueda

    Standard Quantum Limit and Heisenberg Limit in Function Estimation

    Phys. Rev. Lett. 124, 010507 (2020)
  3. K. Kawabata, K. Shiozaki, M. Ueda, and M. Sato

    Symmetry and Topology in Non-Hermitian Physics

    Phys. Rev. X 9, 041015 (2019)
  4. K. Kawabata, S. Higashikawa, Z. Gong, Y. Ashida, and M. Ueda

    Topological unification of time-reversal and particle-hole symmetries in non-Hermitian physics

    Nat. Commun. 10, 297 (2019)
  5. Z. Gong, Y. Ashida, K. Kawabata, K. Takasan, S. Higashikawa, and M. Ueda

    Topological Phases of Non-Hermitian Systems

    Phys. Rev. X 8, 031079 (2018)

Articles

お問い合わせ

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

E-mail:
masahito.ueda[at]riken.jp

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