Manuscript VII-E-ST@1 · VII-E-ST.tex · definition · d28d9c5d

Definition: Coherent recording

Contract E: readout, records, and residuals › Distinct interfaces · lines 356–367

VII-E-ST@1#def:coherent

A fresh quantum carrier $A$ can record the computational basis through

V (∣ z ⟩_{S} \otimes ψ_{B}) = ∣ z ⟩_{S} ∣ z ⟩_{A} \otimes ψ_{B} .

The channel $X \mapsto V X V^{†}$ returns $S, A, B$ . It is not destructive readout and not cloning: $V ∣ + ⟩ = (∣ 00 ⟩ + ∣ 11 ⟩) / 2$ .

Displayed formulas in this passage

unlabeled · line 360
$V (∣ z ⟩_{S} \otimes ψ_{B}) = ∣ z ⟩_{S} ∣ z ⟩_{A} \otimes ψ_{B} .$