TEAM QEDI
EPFL Quantum Hackathon • Quandela Challenge

Hybrid Photonic Temporal QRC
(HPT-QRC)

Swaption Volatility Surface Forecaster

Explore The Solution GitHub Repo

01. The Challenge

Task 1: Predictive Forecasting

Predicting the next H day volatility surface topologies.

Task 2: Data Imputation

Reconstructing missing Option Price nodes in the 2D surface grid.

02. Hybrid Photonic Temporal QRC Architecture

Inspired by Li et al., "QRC for Realized Volatility Forecasting" (2024), we adapted their qubit-based Hamiltonian evolution into a purely Photonic Quantum Reservoir powered by MerLin.

Raw Market Surface
(224D)
Standard
Scaler
PCA (5D)
Rolling 5-Day
Window (1×25)

Hybrid Photonic Temporal QRC
3 Seeds × 3 Virtual Nodes = 9 Circuits
LexGrouping Probability
(90 Quantum Features)
+
Raw Window
(25 Classic Features)
L2 Ridge Regression
Inverse PCA → Inverse Scaler
Day T+1 Swaption Forecast
(224D)
  • 01

    Dedicated Memory Modes

    Instead of mapping data to all spatial modes simultaneously, our temporal array uses 5 input modes and 3 dedicated memory modes. The memory modes are left unencoded, continuously accumulating historical state contexts through serial phase mixing.

  • 02

    Virtual Nodes

    We sample the evolving physical system at multiple structural post-processing depths. These Virtual Nodes emulate capturing chronological measurement sub-intervals (δτ), massively expanding our temporal feature dimensionality without adding physical photon bounds.

  • 03

    Ensemble LexGrouping Compression

    Instead of measuring impossibly vast raw Fock states, we group the probability vectors via LexGrouping across 3 random seeds × 3 virtual depths. By utilizing this Hybrid Photonic Temporal QRC architecture, we massively outperformed our standard formulation!

  • 04

    Direct Target Ridge Forecaster

    Extracting the most prominent Non-linear Mutual Information quantum channels, an L2 regularized Ridge projection predicts the consecutive future states along the latent PCA coordinate axis.

Principal Component Explained Variance

PCA Variance

Temporal Extrapolation: 6-Day Walk-Forward Architecture Performance

Walk Forward Errors

PT-QRC in Action: Tracking Price Trajectory

03. Results vs Classical Baselines

By executing the Hybrid Photonic Temporal QRC pipeline (Li et al., 2024), we successfully beat our underlying standard QRC framework and left classical baseline LSTM networks and quantum regression tools absolutely obsolete.

QSVR
0.0233

RMSE Error

Hybrid QNN
0.0083

RMSE Error

LSTM
0.0073

RMSE Error

Photonic
Linear QRC
0.0065

RMSE Error

Hybrid
Photonic
Linear QRC
0.0028

RMSE Error

Hybrid
Photonic
Temporal
QRC
0.0021

RMSE Error

🥇
Champion
Model

Interactive Model Performance Leaderboard

Performance loss values compared across classical, hybrid, and pure photonic MerLin approaches.

Interactive Error Heatmap (All Horizons)

Interactive Error Grid: (Predicted − Actual) across all 224 features.

Interactive 2D Mean Absolute Error (MAE) Surface Analysis

Tenor vs Maturity Average MAE Grid over the 6-Day Inference Horizon.

QRC Hyperparameter Configuration Impact

Configuration Experiments Matrix

Task 2: Data Imputation Reconstruction Results

Task 2 Imputation Results

Teaching photons to predict the market so we can finally sleep.