Analytical Quantum Complexity RIKEN Hakubi Research Team
RIKEN Hakubi Team Leader: Tomotaka Kuwahara (Ph.D.)
Research Summary
The field of revealing the computational complexity of quantum many-body system simulations when using a classical computer (or quantum computer) is called Hamiltonian Complexity. In particular, from the viewpoint of quantum supremacy of quantum computers and quantum algorithms employing NISQ (i.e., a small quantum computer without error correction), Hamiltonian complexity has become one of the most important research topics in the field of quantum information. Our research aims to solve open mathematical problems in Hamiltonian complexity.
News
From September 1 to 4, Ayumi Ukai participated in the workshop “Dynamics of Entanglement (MMBW01)” at the Isaac Newton Institute in Cambridge, United Kingdom, and presented a poster entitled “On Hastings Factorization for Quantum Many-Body Systems in the Infinite-Volume Setting.”
From August 31 to September 4, Donghoon Kim participated in the 21st Annual Theory of Quantum Computation, Communication and Cryptography (TQC 2026), held in Sherbrooke, Canada, and gave contributed talks on two team projects: “Entanglement area law in interacting bosons: from Bose-Hubbard, φ⁴, and beyond” and “Spectral Small-Incremental Entangling: Breaking Quasi-Polynomial Complexity Barriers in Long-Range Interacting Systems.”
On September 2, the paper “Variational preparation and characterization of chiral spin liquids in quantum circuits” by Donghoon Kim and collaborators was published in Physical Review B.