Efficient Classical Simulation of the DQC1 Circuit with Zero Discord

Quantum 9, 1895 (2025).

https://doi.org/10.22331/q-2025-10-28-1895

A path for efficient classical simulation of the DQC1 circuit that estimates the trace of an implementable unitary under the zero discord condition [17] is presented. This result reinforces the status of non-classical correlations quantified by quantum discord and related measures as the key resource enabling exponential speedups in mixed state quantum computation.