A hardware paper reports a depolarising channel in the form with .
PHYSICS · Multi-part · Fermi University Physics · Quantum Mechanics · Quantum Information & Technology · Open quantum systems, decoherence and error correction
Quantum Information and Technology, Ch Noise as a quantum operation
Problem
A hardware paper reports a depolarising channel in the form (1−p′)ρ+3p′(XρX+YρY+ZρZ) with p′=0.15.
((a)) Convert p′ to the convention Dp(ρ)=(1−p)ρ+pI/2, using p′=3p/4.
((b)) A qubit has Bloch vector r=(0.6,0,0.8). Find its Bloch vector after Dp is applied.