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Adam Pearson

Publications and source records attributed to Adam Pearson.

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A Dynamic-Kernel/QPacket Executable for Quantum Repeater Chains in Q2NS/ns-3

The Quantum Internet operates on entanglement, a non-local, non-copyable, stateful network resource, which motivates protocol organization beyond classical layering. We present a first executable specialization of the Dynamic Kernel/QPacket logic from the beyond-layering protocol suite, targeting entanglement distribution over a linear quantum repeater chain. The implementation builds on Q2NS, an ns-3-based quantum-network simulation module available through the ns-3 App Store. It realizes QPacket meta-headers with service intent and append-only action-commit stamps processed by node-local Dynamic Kernels organized as a Planner--Executor--Engine pipeline, while being deliberately scoped to an analytically verifiable service and policy. Within this scoped setting, we study node heterogeneity through a link-preparation policy that accounts for pre-distributed entanglement and uneven entanglement-generation support across nodes, including delegation via QPacket forwarding. Simulations verify analytical link-resolvability models and expose signaling load, forwarding behavior, and QPacket meta-header growth. Results show that QPacket overhead is shaped by more than just encoding, including policy choices and available network resources. Overall, this study demonstrates how the Q2NS/ns-3 substrate can support reproducible, policy-specific evaluation of quantum-native protocol-suite concepts.

quant-ph

Q2NS Demo: A Quantum Network Simulator Based on ns-3

Q2NS is an open-source quantum network simulator built on ns-3, the de facto standard for classical network simulation. By inheriting ns-3's mature classical stack and event-driven execution model, Q2NS enables faithful co-simulation of quantum-network dynamics and classical signaling, a core requirement for the functioning of any quantum network. Its modular architecture is designed for extensibility, with pluggable quantum-state backends (state-vector, density matrix, stabilizer) and a clean separation between network control and node-level operations. Q2NS comes with a quantum network visualizer Q2NSViz, supporting interactive inspection of both physical- and entanglement-induced connectivity graphs, helping users interpret protocol behavior and entanglement manipulation processes. We present a demonstration of Q2NS, highlighting its ability to capture and simulate the coexistence of quantum and classical communication. The proposed demonstration presents quantum communication scenarios of increasing complexity: from entanglement distribution basics to multipartite graph-state manipulation, complemented by pre-loaded examples in Q2NSViz that require no prior quantum communication or coding experience.

quant-ph

An Extensible Quantum Network Simulator Built on ns-3: Q2NS Design and Evaluation

As quantum networking hardware remains costly and not yet widely accessible, simulation tools are essential for the design and evaluation of quantum network architectures and protocols. However, designing a scalable and computationally efficient quantum network simulator is intrinsically challenging: i) quantum dynamics must be emulated on classical computing platforms while capturing the stateful and non-local nature of entanglement, a quantum resource without any classical networking analog; ii) quantum networking is inherently hybrid, as protocol execution also fundamentally depends on classical signaling. This makes a tight and faithful co-simulation of quantum operations and classical message exchanges a core requirement. In this light, we present Q2NS, a modular and extensible quantum network simulator, built on top of ns-3, designed to seamlessly integrate quantum-network primitives with ns-3's established classical protocol stack. Q2NS adopts a modular architecture that decouples protocol control logic from node- and channel-level operations, enabling rapid prototyping and adaptation across heterogeneous and evolving Quantum Internet scenarios. Q2NS natively supports multiple quantum state representations through a unified interface, allowing interchangeable state-vector, density-matrix, and stabilizer backends. We validate Q2NS through realistic use-case studies and comprehensive benchmarks, demonstrating superior computational efficiency over representative state-of-the-art alternatives, while preserving modeling flexibility. Finally, we provide a dedicated visualization tool that jointly captures physical and entanglement-enabled connectivity and supports entangled-state manipulations, facilitating an intuitive interpretation of entanglement dynamics and protocol behavior. Q2NS offers a flexible, open, and scalable simulation platform for advancing Quantum Internet research.

quant-ph

Analog Errors in Quantum Annealing: Doom and Hope

Quantum annealing has the potential to provide a speedup over classical algorithms in solving optimization problems. Just as for any other quantum device, suppressing Hamiltonian control errors will be necessary before quantum annealers can achieve speedups. Such analog control errors are known to lead to $J$-chaos, wherein the probability of obtaining the optimal solution, encoded as the ground state of the intended Hamiltonian, varies widely depending on the control error. Here, we show that $J$-chaos causes a catastrophic failure of quantum annealing, in that the scaling of the time-to-solution metric becomes worse than that of a deterministic (exhaustive) classical solver. We demonstrate this empirically using random Ising spin glass problems run on the two latest generations of the D-Wave quantum annealers. We then proceed to show that this doomsday scenario can be mitigated using a simple error suppression and correction scheme known as quantum annealing correction (QAC). By using QAC, the time-to-solution scaling of the same D-Wave devices is improved to below that of the classical upper bound, thus restoring hope in the speedup prospects of quantum annealing.

quant-ph