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March 20, 2026

Flying Cat Parity Checks and Modular Fault Tolerant Quantum Computing

A first person tour of McIntyre and Coish's proposal for flying cat parity checks, exploring measurement errors versus photon loss and the path to scalable modular quantum computing.

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Quantum Error Correction Cat Qubits Modular Architectures Parity Checks
March 16, 2026

When Your Qubit Just... Isn't There: Fabrication Imperfections, Qubit Dropouts, and How QEC Fights Back

Exploring the gritty reality of quantum hardware, two-level system defects, and the algorithmic brilliance of routing around broken qubits. A deep dive into Google's LUCI framework and Willow chip results.

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Qubit Dropouts Fabrication Yield Surface Code LUCI Framework Google Quantum AI
March 11, 2026

Concise Constructions of Modular Architectures in Quantum Computing

From Monolithic Chips to Distributed Quantum Networks: Where Does the Boundary Lie? Exploring the taxonomy of modular architectures, entanglement overhead scaling, and where the major industry players sit on the modularity spectrum.

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Modular Architectures Quantum Error Correction Distributed Quantum Computing Surface Codes Entanglement
March 6, 2026

Decoders in Quantum Error Correction: An Overview of Where We Started and Where We Are Heading

An overview of QEC decoders: what the decoding problem actually is, why it is so surprisingly hard, and how the community has made remarkable progress over the past several years.

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Decoders Quantum Error Correction qLDPC Surface Codes Hardware
March 3, 2026

Flag Qubits: The Clever Watchdogs of Fault-Tolerant Quantum Error Correction

How a handful of extra "flag" ancilla qubits can replace expensive verified ancilla states, dramatically reducing the overhead of fault-tolerant syndrome extraction for any stabilizer code.

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Flag Qubits Fault Tolerance Quantum Error Correction Syndrome Extraction Stabilizer Codes
March 1, 2026

Building Quantum Computers Like LEGO: Quantum LDPC Codes for Modular Architectures

A deep dive into the Strikis & Berent construction—how the hypergraph product of connectivity codes gives quantum error-correcting codes that automatically respect modular hardware constraints.

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QLDPC Codes Modular Architectures Hypergraph Product Balanced Product Chain Complexes
February 28, 2026

Lattice Surgery for Quantum Error Correction: From Surface Codes to LDPC Codes and Beyond

Lattice surgery is one of the most powerful techniques in fault-tolerant quantum computing. It allows us to perform logical operations on encoded qubits by merging and splitting code patches—all while preserving the precious error-correcting properties we worked so hard to build.

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Surface Codes Lattice Surgery Fault Tolerance Quantum Error Correction LDPC Codes
February 5, 2026

Optical Distillation Protocols for Spin–Optical Architectures: A Friendly Walk Through Single-Shot GHZ Generation

In this post, I want to unpack a topic that keeps coming back in discussions about modular quantum architectures: how can I get really good multi-partite entanglement between remote modules without drowning myself in slow, error-prone two-qubit gates on memories?

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Quantum Optics GHZ States Distillation Modular Architecture
February 2, 2026

Fault-Tolerance in Quantum Computing: A Comprehensive Exploration of Definitions Across the Field

When I first encountered the term "fault-tolerant" in quantum computing literature, I noticed something puzzling: different researchers seemed to be using it in subtly different ways. In this blog post, I'll walk through the various contexts and definitions of fault-tolerance that have emerged in our quantum computing community.

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Quantum Computing Fault Tolerance Quantum Error Correction Research
January 30, 2026

Entangling Logical Qubits Without Physical Operations: A Simple Guide to Phantom Codes

Phantom codes implement logical CNOT entangling gates using only classical qubit relabelling, achieving zero overhead and perfect fidelity. By placing logical operations at the center of code design, we achieve fault-tolerant entanglement at no physical cost.

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Quantum Error Correction Phantom Codes Fault Tolerance CNOT Gates Zero Overhead
January 27, 2026

Understanding Quantum Error Correction Thresholds: A Practical Guide for Experimentalists

Threshold is one of the most frequently cited concepts in quantum error correction, yet it means different things in different contexts. This article unpacks the various thresholds, explains how they are calculated, and provides practical guidance for interpreting them in the lab.

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Quantum Error Correction Thresholds Fault Tolerance Surface Codes Experimental Physics
January 23, 2026

The Architecture Pyramid: Why Modular Quantum Computers Matter

A deep dive into why one giant quantum computer won't work—and why breaking it apart changes everything about how we build scalable, fault-tolerant quantum systems.

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Quantum Computing Surface Codes Modular Architectures Distributed QC Scalability
January 21, 2026

From Monolithic to Modular: Converting Surface Codes Using Distributed GHZ Measurements

Discover how monolithic surface code circuits can be transformed into fault-tolerant distributed architectures through the power of multipartite GHZ states. This blog explores the mathematical foundation and practical implications of this transformation for scaling quantum computers with modular hardware.

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Quantum Error Correction Surface Codes GHZ States Distributed Quantum Computing Modularity