Curator's Take
This comprehensive review tackles one of quantum computing's most pervasive yet under-discussed challenges: crosstalk between qubits that can silently sabotage quantum computations. While the quantum community often focuses on headline metrics like gate fidelity and coherence times, crosstalk represents a more insidious problem that becomes exponentially worse as systems scale beyond just a few qubits, potentially rendering large quantum computers ineffective regardless of their other specifications. The article's cross-platform analysis is particularly valuable since crosstalk manifests differently across superconducting, trapped ion, and photonic systems, yet most research has remained siloed within specific hardware communities. Perhaps most intriguingly, the authors highlight emerging security vulnerabilities where crosstalk could be exploited as an attack vector, suggesting that what engineers view as a noise problem could become a deliberate tool for quantum cryptanalysis or system compromise.
— Mark Eatherly
Summary
Crosstalk noise derives from phenomena in quantum devices which inhibit individual addressability or cause unintended interactions among qubits. It is widely considered one of the major problems to be solved for a quantum computing platform to operate at scales beyond one or two qubits. Despite this, detailed discussion of crosstalk is often neglected when quantum device performance is described both in the context of device benchmarking and individual algorithm execution. Additionally, while the potential for crosstalk exists in all quantum platforms, the mechanisms and severity of crosstalk between platforms varies significantly, increasing the barrier of entry associated with understanding and performing research on unfamiliar quantum platforms. While previous work focused on theoretical formalism or platform specific details, in this review article, we provide a comprehensive overview of crosstalk from quantum computing literature across a range of physical systems focusing on physical origins, methods of mitigation and known consequential security vulnerabilities. We describe multiple crosstalk mechanisms for all major quantum computing platforms, which are usually implicitly addressed through device design, tuning, and mitigation techniques. We also observe accelerating research regarding security implications, however with multiple avenues for further exploration, especially for non-superconducting systems. Together, this review provides a comprehensive entry point for researchers and industry engineers interested in understanding and addressing the challenges arising from crosstalk phenomena in modern quantum computing systems.