Thermodynamic And Quantum Constraints On Scalable Quantum Computing

QNFO

Standard quantum computing models often assume that error correction can scale indefinitely regardless of operating temperature. However, the thermodynamic constraints on nanoscale systems create a fundamental energy scale mismatch at room temperature that remains unsolved by algorithmic optimizations. Here, a consilience of theoretical thermodynamics, decoherence dynamics, and experimental validation is introduced to delineate the absolute physical boundaries of quantum feasibility. By integrating the Caldeira-Leggett model with relativistic causality constraints, it is demonstrated that atomic-precision quantum computing is thermodynamically impossible above 20 Kelvin. Furthermore, it is identified that while ultra-cryogenic operation (0.1K) offers theoretical scalability, it faces severe engineering bottlenecks from wiring heat loads and thermal boundary resistance (Kapitza resistance). This finding redefines the strategic landscape of quantum computing, establishing cryogenic operation not as an engineering choice but as an immutable physical mandate constrained by thermal logistics.

Machiel Blok, Gabriel Teixeira Landi

Benjamin N Goodberry

Quni-Gudzinas, Rowan Brad

The realization of commercially viable, fault-tolerant quantum computing is precluded not by engineering immaturity but by a fundamental percolation phase transition driven by correlated noise and thermodynamic constraints, which render the required system scales physically uncorrectable.

Anonymous

QNFO

The central tension in quantum computing lies between the exponential scaling of quantum information density and the polynomial limits of cryogenic heat extraction. This thermodynamic bottleneck mandates a paradigm shift from maximizing coherence at millikelvin temperatures to optimizing system-level efficiency through an architectural inversion, where control and readout systems are offloaded to higher-temperature stages. This work validates the physical viability of this approach through a detailed numerical analysis of a quantum unit cell. Grounding the simulation in a realistic noise model and a measurable engineering parameter—the Two-Level System loss tangent—we demonstrate that the systematic improvement of dielectric material quality is the key enabling factor for robust, high-fidelity quantum operations at 4 Kelvin. Our results show that by transitioning from standard amorphous dielectrics to state-of-the-art crystalline materials, the decoherence-limited single-qubit gate fidelity at 4 Kelvin can exceed 99.96%, becoming nearly indistinguishable from the performance at 10 millikelvin. This provides a quantitative, materials-driven roadmap for overcoming the thermodynamic constraints on scalable quantum information systems.