Compare Papers

Paper 1

Low Latency GNN Accelerator for Quantum Error Correction

Alessio Cicero, Luigi Altamura, Moritz Lange, Mats Granath, Pedro Trancoso

Year

2026

Journal

arXiv preprint

DOI

arXiv:2603.22149

arXiv

2603.22149

Quantum computers have the potential to solve certain complex problems in a much more efficient way than classical computers. Nevertheless, current quantum computer implementations are limited by high physical error rates. This issue is addressed by Quantum Error Correction (QEC) codes, which use multiple physical qubits to form a logical qubit to achieve a lower logical error rate, with the surface code being one of the most commonly used. The most time-critical step in this process is interpreting the measurements of the physical qubits to determine which errors have most likely occurred - a task called decoding. Consequently, the main challenge for QEC is to achieve error correction with high accuracy within the tight $1μs$ decoding time budget imposed by superconducting qubits. State-of-the-art QEC approaches trade accuracy for latency. In this work, we propose an FPGA accelerator for a Neural Network based decoder as a way to achieve a lower logical error rate than current methods within the tight time constraint, for code distance up to d=7. We achieved this goal by applying different hardware-aware optimizations to a high-accuracy GNN-based decoder. In addition, we propose several accelerator optimizations leading to the FPGA-based decoder achieving a latency smaller than $1μs$, with a lower error rate compared to the state-of-the-art.

Open paper

Paper 2

STIRAP-Inspired Robust Gates for a Superconducting Dual-Rail Qubit

Ujjawal Singhal, Harsh Vardhan Upadhyay, Irshad Ahmad, Vibhor Singh

Year

2024

Journal

arXiv preprint

DOI

arXiv:2410.04828

arXiv

2410.04828

STImulated Raman Adiabatic Passage (STIRAP) is a powerful technique for robust state transfer capabilities in quantum systems. This method, however encounters challenges for its implementation as a gate in qubit-subspace due to its sensitivity to initial states. By incorporating single-photon detuning into the protocol, the sensitivity to the initial state can effectively be mitigated, enabling STIRAP to operate as a gate. In this study, we experimentally demonstrate the implementation of robust $π$ and $π$/2 rotations in a dual-rail qubit formed by two strongly coupled fixed-frequency transmon qubits. We achieve state preparation fidelity in excess of 0.98 using such rotations. Our analysis reveals these gates exhibit significant resilience to errors. Furthermore, our numerical calculations confirm that these gates can achieve fidelity levels in excess of 0.999. This work suggest a way for realizing quantum gates which are robust against minor drifts in pulse or system parameters.

Open paper