TR2026-129

Base-Preserving APM/Voltage Lifts of Bivariate Bicycle Quantum LDPC Codes

    •  Nourozi, V., Mitchell, D., Koike-Akino, T., "Base-Preserving APM/Voltage Lifts of Bivariate Bicycle Quantum LDPC Codes", IEEE International Conference on Quantum Computing and Engineering (QCE), September 2026.
      BibTeX TR2026-129 PDF
      • @inproceedings{Nourozi2026sep,
      • author = {Nourozi, Vahid and Mitchell, David and Koike-Akino, Toshiaki},
      • title = {{Base-Preserving APM/Voltage Lifts of Bivariate Bicycle Quantum LDPC Codes}},
      • booktitle = {IEEE International Conference on Quantum Computing and Engineering (QCE)},
      • year = 2026,
      • month = sep,
      • url = {https://www.merl.com/publications/TR2026-129}
      • }
  • MERL Contact:
  • Research Area:

    Signal Processing

Abstract:

Bivariate-bicycle (BB) quantum LDPC codes are compact Calderbank–Shor–Steane (CSS) codes with sparse checks and strong finite-length performance. Standard BB codes represent each monomial x^a * y^b by a two-coordinate circulant permutation matrix, so that the CSS condition follows from commutation of the x and y shifts. We summarize a basepreserving affine-permutation/voltage-lift extension of BB codes. Each base monomial is replaced by a lifted monomial acting on a three-coordinate permutation. The novelty is the BB-compatible use of these lifted monomials. We demonstrate that the voltage lifting can effectively remove short cycles.

 

  • Related News & Events

    •  NEWS    MERL Presents Five Papers at IEEE Quantum Week 2026
      Date: September 13, 2026 - September 18, 2026
      Where: Toronto, Canada
      MERL Contact: Toshiaki Koike-Akino
      Research Areas: Applied Physics, Artificial Intelligence, Machine Learning, Optimization, Signal Processing
      Brief
      • MERL is pleased to announce that five papers have been accepted to the 2026 IEEE International Conference on Quantum Computing and Engineering (QCE), also known as IEEE Quantum Week 2026, held September 13–18, 2026, in Toronto, Canada.

        The papers highlight MERL’s recent advances in quantum computing, spanning hardware-efficient quantum state preparation, quantum low-density parity-check (QLDPC) code design, graph-cover-based code construction, machine-learning-assisted code search, and reinforcement-learning-guided quantum error correction. Together, these works address important challenges toward more efficient and reliable quantum computing systems.

        The five papers are:
        - “Near-Lower-Bound Approximate Quantum State Preparation with Hardware-Efficient Circuits” — Toshiaki Koike-Akino (TR2026-131)
        - “Reinforcement-Learning-Guided Multi-Branch Decoding of Quantum LDPC Codes” — Vahid Nourozi, Toshiaki Koike-Akino, and David Mitchell (TR2026-130)
        - “Q-Learning Base Search Voltage-Labeled Covers for Weight-Six Bivariate-Bicycle Quantum LDPC Codes” — Vahid Nourozi, David Mitchell, and Toshiaki Koike-Akino (TR2026-132)
        - “Collision-Voltage Design of Directional Covers for Bivariate Bicycle Quantum LDPC Codes” — Vahid Nourozi, David Mitchell, and Toshiaki Koike-Akino (TR2026-133)
        - “Base-Preserving APM/Voltage Lifts of Bivariate Bicycle Quantum LDPC Codes” — Vahid Nourozi, David Mitchell, and Toshiaki Koike-Akino (TR2026-129)
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