Hayato Goto
Quantum Computer Architecture Research Team Team Leader
Outline
We do theoretical research on the total design of quantum computers, from the approaches to fault-tolerant quantum computation (FTQC) to their physical implementations, namely, quantum computer architecture. The research on quantum computer architecture requires to consider all aspects of quantum computers. The requirement of large resource overheads for FTQC is a central problem at present. To solve this problem, we focus on high-rate codes. Most approaches to FTQC use the encoding of a logical qubit into many physical qubits, which leads to the resource problem. There exist high-rate codes encoding multiple logical qubits at once, but FTQC with them has not been established. We aim at solving the resource problem by developing FTQC with high-rate codes.
Representative Research Results
・ H. Goto, “Minimizing resource overheads for fault-tolerant preparation of encoded states of the Steane code”, Sci. Rep., 6, 19578 (2016).
・ H. Goto, “Step-by-step magic state encoding for efficient fault-tolerant quantum computation”, Sci. Rep., 4, 7501 (2014).
・ H. Goto and H. Uchikawa, “Soft-decision decoder for quantum erasure and probabilistic-gate error models”, Phys. Rev. A, 89, 022322 (2014).
・ H. Goto and H. Uchikawa, “Fault-tolerant quantum computation with a soft-decision decoder for error correction and detection by teleportation”, Sci. Rep., 3, 2044 (2013).
・ H. Goto and K. Ichimura, “Fault-tolerant quantum computation with probabilistic two-qubit gates”, Phys. Rev. A, 80, 040303(R) (2009).
Quantum computer architecture
Conventional single-logical-qubit encoding (Left), high-rate code (Right).