IQC student seminar featuring Tan Yi Da

Tan Yi Da

Several natural quantifiers of how far a quantum channel is from being reversible — a KL-deviation measure, the dual map infidelity, the Petz map infidelity, and the optimal infidelity — all satisfy the standard axioms, yet rank channels differently in parts of parameter space. Evaluating these on the bit-flip, amplitude-damping, and depolarizing qubit channels, I show that the orderings flip in certain parameter regions: when comparing two channels, the quantifiers can disagree on which one is more irreversible. This talk covers where these flips occur and what that means for comparing channels.

Location 

QNC 1201