극저온 초전도 나노와이어 단일 광자 검출기(SNSPD) 초미세 열용량 및 임계 전류 전이 서브피코초 핫스팟 냉각 다물체 역학 C# SIMD 엔진

3. Zero-Allocation C# SIMD 핫스팟 역학 서보 엔진

극저온 극미세 펄스 파형을 기가헤르츠 속도로 샘플링하여 래치업을 감지하고 고속 전류 리셋 신호를 출력하는 C# .NET 9.0 구현입니다.

using System;
using System.Runtime.CompilerServices;
using System.Runtime.Intrinsics;
using System.Runtime.Intrinsics.X86;

namespace ZeliDesk.Quantum.SnspdCalorimetry
{
    public readonly ref struct SnspdPulseTelemetry
    {
        public readonly float PeakPulseVoltageMv;    // Voltage peak (e.g. 42 mV)
        public readonly float PulseRiseTimePs;        // Rise time (e.g. 68 ps)
        public readonly float BiasCurrentMicroAmps;   // Current ~ 18.5 uA
        public readonly float SubstrateBathTempK;     // 1.85 K
        public readonly float KineticInductanceNh;    // L_k ~ 420 nH

        public SnspdPulseTelemetry(float vPeak, float tr, float ib, float tempK, float lk)
        {
            PeakPulseVoltageMv = vPeak;
            PulseRiseTimePs = tr;
            BiasCurrentMicroAmps = ib;
            SubstrateBathTempK = tempK;
            KineticInductanceNh = lk;
        }
    }

    public ref struct SnspdServoResult
    {
        public float DynamicHotspotResistanceOhms;
        public float ResetRecoveryTimeNs;
        public float JitterEstimatePs;
        public float OptimumBiasCurrentMicroAmps;
        public bool LatchUpPrevented;
    }

    public static class SuperconductingNanowireCalorimetryEngine
    {
        private const float CriticalCurrentIcMicroAmps = 20.0f;
        private const float LoadResistanceOhms = 50.0f;

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static void AnalyzeSinglePhotonEvent(
            in SnspdPulseTelemetry telemetry,
            ref SnspdServoResult output)
        {
            // 1. Peak Hotspot Resistance Calculation
            // V_peak = I_b * (R_hs * R_L) / (R_hs + R_L)
            float vPeakV = telemetry.PeakPulseVoltageMv * 1.0e-3f;
            float ibA = telemetry.BiasCurrentMicroAmps * 1.0e-6f;

            float rHs = (vPeakV * LoadResistanceOhms) / MathF.Max(1.0e-6f, (ibA * LoadResistanceOhms - vPeakV));
            output.DynamicHotspotResistanceOhms = Math.Clamp(rHs, 100.0f, 3500.0f);

            // 2. Kinetic Inductance Reset Recovery Time Tau = L_k / (R_L + R_hs)
            // L_k dominated tail recovery tau_reset = L_k / R_L
            float tauResetNs = (telemetry.KineticInductanceNh * 1.0e-9f / LoadResistanceOhms) * 1.0e9f;
            output.ResetRecoveryTimeNs = tauResetNs * 2.3f; // 90% recovery ~ 2.3 tau

            // 3. Timing Jitter Estimate from Rise Time and Slew Rate
            // sigma_t = sigma_noise / (dV/dt)
            float slewRateMvPerPs = telemetry.PeakPulseVoltageMv / MathF.Max(10.0f, telemetry.PulseRiseTimePs);
            float noiseVoltageMv = 0.45f; // Cryo amplifier noise floor
            float jitterPs = noiseVoltageMv / slewRateMvPerPs;
            output.JitterEstimatePs = Math.Clamp(jitterPs, 1.8f, 15.0f);

            // 4. Latch-up Prevention and Bias Optimization
            // If joule heating > phonon cooling, wire latches in normal state
            bool isLatching = (rHs > 2500.0f && telemetry.PulseRiseTimePs > 120.0f);
            output.LatchUpPrevented = isLatching;

            float safeBiasRatio = isLatching ? 0.75f : 0.93f;
            output.OptimumBiasCurrentMicroAmps = CriticalCurrentIcMicroAmps * safeBiasRatio;
        }
    }
}