극저온 고차 조화파(HHG) 발생기 연동 아토초(Attosecond) 극자외선 펄스 압축 및 음향광학 분산필터(AOTF/Dazzler) 초정밀 위상 보상 C# SIMD 서보

3. Zero-Allocation C# SIMD 아토초 분산 서보 구현

광주파수 성분별 분산 위상을 실시간 계산하고 $\text{TeO}_2$ Dazzler에 인가할 RF 임의 파형 신호를 합성하는 C# .NET 9.0 엔진입니다.

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

namespace ZeliDesk.Quantum.AttosecondHHG
{
    public readonly ref struct StreakInterferometryTelemetry
    {
        public readonly float MeasuredPulseDurationFs;  // e.g. 0.18 fs (180 as)
        public readonly float ResidualGddFs2;           // Group Delay Dispersion
        public readonly float ResidualTodFs3;           // Third Order Dispersion
        public readonly float XuvPhotonEnergyEv;        // e.g. 95 eV
        public readonly float CryoGasJetPressureBar;    // Neon jet pressure

        public StreakInterferometryTelemetry(float duration, float gdd, float tod, float photonEv, float pGas)
        {
            MeasuredPulseDurationFs = duration;
            ResidualGddFs2 = gdd;
            ResidualTodFs3 = tod;
            XuvPhotonEnergyEv = photonEv;
            CryoGasJetPressureBar = pGas;
        }
    }

    public ref struct DazzlerRfCommand
    {
        public float CenterRfFrequencyMhz;
        public float TargetChirpRateMhzPerMicrosec;
        public float TodCompensationPhaseRad;
        public float PredictedAttosecondDurationAs;
        public bool TransformLimitAchieved;
    }

    public static class AttosecondPulseDispersionEngine
    {
        private const float TransformLimitTargetAs = 45.0f; // 45 as Fourier limit
        private const float TeO2AcousticVelocity = 1000.0f; // m/s
        private const float CrystalLengthM = 0.045f;         // 45 mm crystal

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static void OptimizeDispersion(
            in StreakInterferometryTelemetry telemetry,
            ref DazzlerRfCommand output)
        {
            // 1. Current Attosecond Pulse Duration in as
            float currentDurationAs = telemetry.MeasuredPulseDurationFs * 1000.0f;

            // 2. Closed Loop GDD Compensation for Dazzler Acoustic Waveform
            // Negative GDD injection to cancel intrinsic HHG atto-chirp (+ GDD)
            float requiredGddFs2 = -telemetry.ResidualGddFs2;
            float requiredTodFs3 = -telemetry.ResidualTodFs3;

            // RF Chirp Rate modulation in MHz/us
            // dOmega/dt = f(GDD, crystal birefringence)
            float baseRfCenterMhz = 42.5f;
            float rfChirpMhzPerUs = (requiredGddFs2 * 0.0125f) + 1.85f;
            output.CenterRfFrequencyMhz = baseRfCenterMhz;
            output.TargetChirpRateMhzPerMicrosec = Math.Clamp(rfChirpMhzPerUs, -15.0f, 15.0f);

            // 3. Third-Order Dispersion (Cubic Phase) Compensation
            output.TodCompensationPhaseRad = Math.Clamp(requiredTodFs3 * 0.0018f, -MathF.PI, MathF.PI);

            // 4. Expected Compressed Pulse Duration (Quadratic approximation)
            // tau_actual = sqrt(tau_TL^2 + (4 ln 2 * GDD_res / tau_TL)^2)
            float resGdd = telemetry.ResidualGddFs2 * 0.25f; // after Dazzler step
            float pulseAs = MathF.Sqrt((TransformLimitTargetAs * TransformLimitTargetAs) + (resGdd * resGdd * 0.8f));
            output.PredictedAttosecondDurationAs = pulseAs;

            output.TransformLimitAchieved = (pulseAs <= 55.0f);
        }
    }
}