Quantum Advantage of Thermal Quantum Dot Model in Preserving Correlations Under Ohmic Reservoir Noise

Abstract The open quantum dynamics of a two‐qubit quantum dot system is investigated initially prepared as thermal state and exposed to an Ohmic bosonic reservoir, modeling it as a prototype quantum processor. By integrating local and interaction Hamiltonians, field‐induced couplings, and thermal effects, we derive the system's thermal state and analyze its evolution using quantum measures: concurrence, Bell nonlocality, energy fluctuations, and quantum speed limit (QSL) time. Results reveal that strong field‐induced coupling enhances and preserves quantum correlations, which otherwise vanish abruptly beyond a critical coupling strength. Conversely, energy fluctuations and the QSL time are suppressed for weak coupling but increase significantly in the strong coupling regime. Higher temperatures are shown to uniformly accelerate the dissipation of quantum correlations. Furthermore, it is found that while weak splitting strength allows for tunable correlations, strong splitting enhances initial correlations and energy fluctuations at the cost of suppressing the QSL. These findings demonstrate the potential of coupled quantum dots as tunable two‐qubit processors, providing a guide for precise control over their quantum and thermal properties.