NONLINEAR PHASE STABILIZATION IN QUANTUM INFORMATION SYSTEMS: A TEMPORAL PHASE-LOCKED LOOP FRAMEWORK BASED ON LA-ODR TEMPORAL SUSCEPTIBILITY FEEDBACK
Andriy V Lemeshko, Isamu Ohnishi
Abstract: The scalability of Noisy Intermediate-Scale Quantum (NISQ) devices remains fundamentally limited by decoherence, which conventional dynamical decoupling and quantum error correction only partially mitigate. This paper presents a transition from passive noise suppression to active dynamical stabilization through controlled modulation of the effective state-space metric. Within the Lie-algebraic observable-dependent renormalization (LA-ODR) framework, we introduce the Temporal Phase-Locked Loop (TPLL) — an active feedback controller that drives the temporal susceptibility χ_τ toward the globally stable fixed point χ_τ* = λ_nat/(λ_ctrl + λ_nat) via the Kyiv–Ohnishi hybrid flow: dχ_τ/dt = −α·Γ₀·(χ_τ)^(β+1) − λ_ctrl·χ_τ + λ_nat·(1−χ_τ). Numerical simulations demonstrate the emergence of metastable coherence plateaus extending coherence times from ~100 µs to ~1.5 ms under realistic hardware benchmarks (FPGA latency Δt < 500 ns). Three operationally distinct zones are characterized by χ_τ thresholds, and two experimentally distinguishable signatures — Phase Inertia and Avalanche Collapse — are predicted. The TPLL is compared with dynamical decoupling, quantum error correction, and discrete time crystals, establishing complementarity rather than competition. The mathematical foundations rest on four global stability theorems via Lyapunov analysis and Chiba renormalization-group flow. Index Terms: Quantum coherence; decoherence control; temporal susceptibility; LA-ODR; Temporal Phase-Locked Loop (TPLL); Kyiv–Ohnishi flow; NISQ devices; open quantum systems; Lyapunov stability; Lie algebra; FPGA quantum control; nonlinear dynamics.
•Jun 26, 2026•0 citations