活動公告

【演講公告】2026/09/04 Scaling up superconducting quantum circuits with tileable qubit architecture-Eisuke Abe

Title:  Scaling up superconducting quantum circuits with tileable qubit architecture
Speaker: Eisuke Abe (RIKEN Center for Quantum Computing)
Time: September 4 (Fri.), 11:00
Venue: 2F Conference Room, RCCI

 

The development of quantum computers is now in full swing in both atomic and solid-state systems. In the case of superconducting system, the first coherent control of a so-called Cooper-pair box was demonstrated more than a quarter century ago, and consecutive efforts to improve design, materials, control theory since then have led to recent dramatic increases in the number of available qubits (more than a hundred), the qubit coherence (longer than a millisecond), and the control fidelity (better than 99.9% in two-qubit gates). To scale up a superconducting system, one of the key challenges is how to deliver microwave signals to the individual qubits that are just a few hundred microns apart in a two-dimensional chip. To address this issue, we adopt a tileable square-lattice qubit architecture with the coaxial cables addressing the backside of the chip from the vertical direction. In this talk, I will discuss the chip design, three-dimensional integrated wiring and performance of integrated chips of superconducting quantum computers developed at RIKEN Center for Quantum Computing, namely, a 64-qubit system named ''A'' and a 144-qubit system named ''A-II'', now both deployed for cloud service.