Quantum Decoherence via Environment Coupling
Bloch vector shrinks as qubit entangles with environment — quantum → classical
Coupling strength γ:
0.50
Temperature kT:
0.50
Initial θ (Bloch polar):
90°
Reset
ρ(t) = e^{-γt} ρ_off + diag mix
Decoherence time τ_D = 1/γ
Off-diagonal: ρ₀₁(t) = ρ₀₁(0)e^{−γt}
Bloch vector length → 0 as t→∞