Manuscript En03-A@1 · En03-A.tex · definition · 5398614e

Definition: Coherent recording

Typed interfaces and semantic configurations › Three measurement interfaces · lines 390–403

En03-A@1#def:recording, En03-A@1#eq:copy-isometry

A fresh quantum carrier $A$ , with basis indexed by $Z$ , is introduced by the isometry

V : H_{S B} ⟶ H_{S A B}, V (∣ z ⟩_{S} \otimes ∣ b ⟩_{B}) = ∣ z ⟩_{S} \otimes ∣ z ⟩_{A} \otimes ∣ b ⟩_{B} .

Its channel is $Copy_{S} (ρ) = V ρ V^{†}$ . For qubits it is zero preparation followed by CNOT.

Displayed formulas in this passage

En03-A@1#eq:copy-isometry · line 394
$V : H_{S B} ⟶ H_{S A B}, V (∣ z ⟩_{S} \otimes ∣ b ⟩_{B}) = ∣ z ⟩_{S} \otimes ∣ z ⟩_{A} \otimes ∣ b ⟩_{B} .$