Collective advantages in qubit reset: effect of coherent qubits

Abstract

The Landauer principle sets a lower bound on the thermodynamic cost of qubit reset, which is only attainable for the quasistatic process. In this Letter, we explore the collective advantage of qubit reset of coherent qubits in three aspects. First, for the quasistatic process, the thermodynamic cost of collective reset is remarkably lower than parallel reset because of the reduced Hilbert space dimension due to entanglement effects. Second, for the finite-time qubit reset, we prove that the error probability fades away and per-qubit heat production tends the Landauer bound for initially continuous protocols in the thermodynamic limit. Third, we show that qubit reset performance enhances with the increase in the number of qubits. Our results, illustrated by different protocols, provide a blueprint for future quantum device fabrication.