Hybrid Analog-Digital Quantum Processor Architecture for Mid-Scale Fault Tolerance

Hybrid Analog-Digital Quantum Processor Architecture for Mid-Scale Fault Tolerance | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Hybrid Analog-Digital Quantum Processor Architecture for Mid-Scale Fault Tolerance Hemanth Kumar Manchabale Papachappa This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8089366/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The immense resource overhead of full quantum error correction (QEC) presents a formidable barrier to achieving fault-tolerant quantum computation. This paper introduces a hybrid analog-digital quantum processor architecture designed as a pragmatic strategy for achieving "mid-scale fault tolerance" (MSFT). We formally define MSFT as a hardware-level error suppression scheme that achieves a fidelity gain by replacing deep, error-prone digital gate sequences with single, high-fidelity analog evolution blocks. The architecture comprises a programmable digital core for state preparation and measurement, coupled to an analog co-processor that executes computationally intensive Hamiltonian evolutions. This approach reduces the effective logical depth and error accumulation for algorithms like VQE. We validate this claim with statistically robust simulations on standard molecular Hamiltonians (LiH and BeH₂), demonstrating a significant performance advantage over purely digital systems based on an aggregation of 50 independent simulation trials. The analysis includes scalability and a discussion of the critical digital-analog interface, proposing trapped-ion and neutral-atom systems as viable physical platforms. Quantum Computing Hybrid Quantum Systems Fault Tolerance Error Mitigation Analog Quantum Simulation VQE. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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