Witnessing quantum resource conversion within deterministic quantum computation using one pure superconducting qubit

TL;DR

This paper demonstrates the implementation of deterministic quantum computation with one qubit (DQC1) in a superconducting system, showing how coherence is converted into discord, and highlights the platform's potential for studying quantum resource dynamics.

Contribution

First experimental realization of DQC1 in superconducting circuits, tracking coherence and discord dynamics, and revealing resource conversion during quantum computation.

Findings

DQC1 can be implemented in superconducting qubits.

Coherence is converted into discord during DQC1.

Superconducting circuits are effective for studying quantum resource dynamics.

Abstract

Deterministic quantum computation with one qubit (DQC1) is iconic in highlighting that exponential quantum speedup may be achieved with negligible entanglement. Its discovery catalyzed heated study of general quantum resources, and various conjectures regarding their role in DQC1's performance advantage. Coherence and discord are prominent candidates, respectively characterizing non-classicality within localized and correlated systems. Here we realize DQC1 within a superconducting system, engineered such that the dynamics of coherence and discord can be tracked throughout its execution. We experimentally confirm that DQC1 acts as a resource converter, consuming coherence to generate discord during its operation. Our results highlight superconducting circuits as a promising platform for both realizing DQC1 and related algorithms, and experimentally characterizing resource dynamics within quantum protocols.