INJEQT: Improved Magic-State Injection Protocol for Fault-Tolerant Quantum Extractor Architectures

• URL: http://arxiv.org/abs/2604.25094v1
• Date: Tue, 28 Apr 2026 00:58:22 GMT
• Title: INJEQT: Improved Magic-State Injection Protocol for Fault-Tolerant Quantum Extractor Architectures
• Abstract summary: Near-term FTQC system designs are constrained by limited error budgets and largely sequential execution of non-Clifford gates.<n>In this work, we study the extractor architecture, a recently proposed FTQC design that enables universal quantum computation on spatially-efficient QEC codes.
• Score: 2.8939699256527276
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Near-term FTQC system designs are constrained by limited error budgets and largely sequential execution of non-Clifford gates. As a result, reducing the number of the most-error prone instructions becomes critical for successful program execution. In this work, we study the extractor architecture, a recently proposed FTQC design that enables universal quantum computation on spatially-efficient QEC codes such as the BB code family. In these architectures, over $90\%$ of the total program error arises from the synthillation process, which involves $\lvert T\rangle$-state preparation and injection to implement non-Clifford gates. We observe that standard Rz synthillation requires multiple sequential $\lvert T\rangle$-state injections, each incurring an inter-module measurements, the most expensive instruction in the architecture, which cumulatively dominate the overall error budget. To address this bottleneck, we propose INJEQT, a $2$-factory design that uses an auxiliary code capable of synthesizing $Rz(θ)$ states with lower error rates. These states are then injected into the extractor modules using only a constant number of inter-module measurements. This approach reduces overall error rates by up to $22\times$. We further reduce the time overhead by a pre-fetching strategy that prepares the Rz states and their correction states in parallel. This approach improves the wall-clock time by up to $13\times$ and reduces the space-time cost by up to $7.2\times$, for an optimal choice of the number of INJEQT factories for each metric. We evaluate INJEQT for multiple state preparation techniques such as distillation, cultivation and STAR, and model the execution times for both lattice surgery-based and transversal CNOT based injections. Our results demonstrate that INJEQT is robust across factory choices and device technologies, enabling more efficient architectural designs for FTQC.

Related papers

• Fault-tolerant $|\sqrt{ \mathrm{T} }\ angle$ state preparation and injection for more efficient fine-grained quantum circuit synthesis [0.9744114320491685]
  We introduce flag fault-tolerant protocols for preparing logical $|sqrtmathrmT rangle $ magic states on the 3D tetrahedral color code.<n>We find that access to $sqrtmathrmT$ reduces the average space-time cost of synthesizing Haar-random single-qubit unitaries by approximately $20$-$30$%.
  arXiv  Detail & Related papers  (2026-08-26T13:48:38Z)
• SSTQ:Privacy-Preserving Vector Quantization via Subsampled Stochastic TurboQuant [79.24089819400126]
  Subsampled TurboQuant (SSTQ) is a framework that combines overcomplete equal-width tight frames, coordinate subsampling, and privacy-aware quantization.<n>SSTQ achieves mean squared error scaling while using only $lceil log N il + b$ bits per client, where $N = (d)$ is the frame size.<n>We also derive a surrogate privacy-aware codebook objective that reduces the codebook-dependent MSE scaling from $O(4b)$ to $O(2b)$.
  arXiv  Detail & Related papers  (2026-08-05T17:51:25Z)
• General circuit compilation protocol into partially fault-tolerant quantum computing architecture [0.0]
  We propose a circuit execution protocol for the space-time efficient analog rotation (STAR) architecture.<n>Our protocol aims to reduce such time overhead by parallel trials of resource state creations and more frequent trials of joint measurements.
  arXiv  Detail & Related papers  (2026-03-18T07:08:56Z)
• Beyond Test-Time Training: Learning to Reason via Hardware-Efficient Optimal Control [86.63490309209378]
  We formulate reasoning as optimal control and introduce the Test-Time Control layer, which performs finite-horizon LQR planning over latent states at inference time.<n>We demonstrate that embedding optimal control as an architectural layer provides an effective and scalable mechanism for reasoning beyond test-time training.
  arXiv  Detail & Related papers  (2026-03-10T05:42:13Z)
• A Scalable Distributed Quantum Optimization Framework via Factor Graph Paradigm [46.08923284345648]
  We introduce a structure-aware framework for distributed quantum optimization.<n>We find that for a search space of size $N$, our framework achieves $O(sqrtN)$ query complexity up to processors and separator dependent factors.<n>We show that structure-aware decomposition delivers a practical path to scalable distributed quantum optimization on quantum networks.
  arXiv  Detail & Related papers  (2026-03-08T15:15:52Z)
• PT$^2$-LLM: Post-Training Ternarization for Large Language Models [52.4629647715623]
  Large Language Models (LLMs) have shown impressive capabilities across diverse tasks, but their large memory and compute demands hinder deployment.<n>We propose PT$2$-LLM, a post-training ternarization framework tailored for LLMs.<n>At its core is an Asymmetric Ternary Quantizer equipped with a two-stage refinement pipeline.
  arXiv  Detail & Related papers  (2025-09-27T03:01:48Z)
• Optimizing Multi-level Magic State Factories for Fault-Tolerant Quantum Architectures [0.8453577061453568]
  We consider a concept architecture comprising a dedicated zone as a multi-level magic state factory and a core processor for efficient logical operations.<n>We show that physical quantum resource estimation reduces to a simple model involving a small number of key parameters.
  arXiv  Detail & Related papers  (2024-11-06T21:25:34Z)
• Compilation of Trotter-Based Time Evolution for Partially Fault-Tolerant Quantum Computing Architecture [0.6449786007855248]
  We present an efficient method for simulating the time evolution of the 2D Hubbard model Hamiltonian. Our analysis reveals an acceleration of over 10 times compared to naive serial compilation. For devices with a physical error rate of $p_rm phys = 10-4$, we estimate that approximately $6.5 times 104$ physical qubits are required to achieve faster ground state energy estimation.
  arXiv  Detail & Related papers  (2024-08-27T10:07:34Z)
• Practical quantum advantage on partially fault-tolerant quantum computer [0.6449786007855248]
  We propose an alternative approach to achieve practical quantum advantages on early-FTQC devices. Our framework is based on partially fault-tolerant logical operations to minimize spatial overhead. We present several promising applications that leverage the potential of our framework.
  arXiv  Detail & Related papers  (2024-08-27T07:58:09Z)
• Transversal Injection: A method for direct encoding of ancilla states for non-Clifford gates using stabiliser codes [55.90903601048249]
  We introduce a protocol to potentially reduce this overhead for non-Clifford gates. Preliminary results hint at high quality fidelities at larger distances.
  arXiv  Detail & Related papers  (2022-11-18T06:03:10Z)
• Matching Pursuit Based Scheduling for Over-the-Air Federated Learning [67.59503935237676]
  This paper develops a class of low-complexity device scheduling algorithms for over-the-air learning via the method of federated learning. Compared to the state-of-the-art proposed scheme, the proposed scheme poses a drastically lower efficiency system. The efficiency of the proposed scheme is confirmed via experiments on the CIFAR dataset.
  arXiv  Detail & Related papers  (2022-06-14T08:14:14Z)
• AQD: Towards Accurate Fully-Quantized Object Detection [94.06347866374927]
  We propose an Accurate Quantized object Detection solution, termed AQD, to get rid of floating-point computation. Our AQD achieves comparable or even better performance compared with the full-precision counterpart under extremely low-bit schemes.
  arXiv  Detail & Related papers  (2020-07-14T09:07:29Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.