The 287th R-CCS Cafe (Mar 2, 2026)

TOP Events & Outreach R-CCS Cafe The 287th R-CCS Cafe (Mar 2, 2026)

Details
Date	Mon, Mar 2, 2026
Time	3:00 pm - 4:30 pm (3:00 pm - 4:00 pm three talks, 4:00 pm - 4:30 pm Free discussion)
City	Kobe, Japan/Online
Place	Lecture Hall (6th floor) at R-CCS, Online seminar on Zoom If you are not affiliated with R-CCS and would like to attend R-CCS Cafe, please email us at r-ccs-cafe[at]ml.riken.jp.
Language	Presentation Language: English Presentation Material: English
Speakers	Maxence Vandromme Quantum-HPC Hybrid Software Environment Unit Research Scientist Masahiro O. Takahashi Computational Materials Science Research Team JSPS PD Researcher Boma Anantasatya Adhi Processor Research Team Research Scientist

Talk Titles and Abstracts

1st Speaker: Maxence Vandromme

Title:

Training a Quantum Machine Learning model on real quantum hardware

Abstract:

Quantum Machine Learning (QML) aims to study the possible ways to combine Machine Learning methods with Quantum Computing. We focus here on using the higher expressivity of quantum circuits to improve the quality of the final model. Although promising for some applications, training a QML model requires too many quantum circuit evaluations to be feasible on real hardware, even for very small datasets. As such, these methods remain confined to simulators, which limits their ability to generalize. Post-Variational Quantum Neural Networks (QNN) are a recent type of algorithm which require significantly fewer circuit evaluations compared to other methods. We implemented this algorithm on a RIKEN's HPC-QC system using the Fugaku supercomputer linked to two different quantum machines (superconducting and ion-trap), and showed that Post-Variational QNNs can be trained in reasonable time on real hardware.

2nd Speaker: Masahiro O. Takahashi

Title:

Signatures of PT-symmetry breaking in quench dynamics using a superconducting quantum computer

Abstract:

A quantum quench probes nonequilibrium many-body dynamics following a sudden change in the Hamiltonian. We investigate quench dynamics in a non-Hermitian interacting spin system using superconducting quantum processors. The target is the Yang–Lee model—a transverse-field Ising model with a local imaginary longitudinal field—which exhibits parity–time (PT) symmetry and hosts both PT-unbroken and PT-broken phases. To implement non-unitary dynamics, we introduce ancilla qubits and post-selection to realize effective non-unitary evolution. Using IBM Quantum processors (Heron r3), we measure the relaxation of local spin moments after a quench and reconstruct the PT phase diagram for a small system. The phase boundary agrees with exact diagonalization, demonstrating the feasibility of superconducting quantum hardware for non-Hermitian many-body dynamics.

3rd Speaker: Boma Anantasatya Adhi

Title:

Towards Unified AI and HPC Accelerators: Design and Optimization of RIKEN CGRA

Abstract:

Coarse-grained reconfigurable arrays (CGRAs) are promising post-Moore accelerators for scaling performance in High-Performance Computing (HPC) and Artificial Intelligence (AI). However, fully understanding and realizing the benefits CGRAs bring to these demanding workloads is an open research question. This presentation highlights our past and future design-space explorations to optimize our CGRA architecture specifically for HPC and AI applications.

Important Notes

Please turn off your video and microphone when you join the meeting.
The broadcasting may be interrupted or terminated depending on the network condition or any other unexpected event.
The program schedule and contents may be modified without prior notice.
Depending on the utilized device and network environment, it may not be able to watch the session.
All rights concerning the broadcasted material will belong to the organizer and the presenters, and it is prohibited to copy, modify, or redistribute the total or a part of the broadcasted material without the previous permission of RIKEN.

（Feb 25, 2026）