Ultrafast Reconfigurable Topological Photonic Processing Accelerator

This paper presents the development of a non-volatile topological photonic computing (NTPC) chip, which integrates topological modulators on a 4-inch PZT thin-film platform. This chip leverages the high-speed electro-optic response and non-volatility of ferroelectric lead zirconate titanate (PZT) to enable ultrafast reconfiguration, high computational density, and zero static power consumption, making it a promising platform for next-generation photonic tensor processing.

Key Contributions:

1. High Computational Density and Speed: The NTPC achieves 266 TOPS/mm² in computational density, with a throughput of 1.92 TOPS. It outperforms existing silicon photonic reconfigurable chips by two orders of magnitude and thin-film lithium niobate platforms by four orders of magnitude. This dense computational capacity allows for tasks like image processing and solving time-varying partial differential equations (PDEs) with high accuracy (e.g., 95.64% for handwritten digit recognition on the MNIST dataset).

2. Non-Volatility and Reconfigurability: One of the key features of the NTPC is its non-volatile reconfigurability. This enables it to perform dynamic reconfiguration with zero static power consumption, making it highly energy-efficient. PZT’s non-volatile characteristics enable precise control over the refractive index, which is crucial for adjusting the optical path without significant power overhead.

3. Wavelength-Space Multiplexing: The NTPC chip integrates 16-channel wavelength-space multiplexing (WDM and SDM), allowing for parallel processing with four wavelengths and four spatial modes. This design facilitates high-speed, high-throughput computations, which is a key advantage for optical tensor processing.

4. Applications: The NTPC demonstrates significant improvements in several computing tasks, including:

• Image edge detection and sharpening using optical convolution.

• Handwritten digit classification with 95.64% accuracy, offering 13.08 ns processing time per image.

• Time-dependent PDE solving, such as heat transfer simulations, with 94.5% accuracy.

5. Reconfigurable Optical I/O for High Bandwidth: The NTPC also supports dense wavelength division multiplexing (DWDM), achieving a 3.56 Tbps/mm bandwidth density on a compact 0.225-mm footprint. This is significantly higher than other optical I/O solutions, demonstrating the NTPC's potential for optical interconnects in disaggregated data centers and other high-speed optical systems.

6. Energy Efficiency: The NTPC demonstrates 265 fJ/operation energy efficiency, making it highly suitable for scalable integration. It achieves ultra-low power consumption, drastically reducing the energy overhead compared to conventional approaches like thermo-optic tuning, which consume much more power.

Conclusion:

This work establishes the NTPC as a high-speed, non-volatile platform that significantly advances the field of photonic computing. By integrating topological photonic crystal modulators with PZT thin films, the NTPC demonstrates groundbreaking performance in computational density, reconfigurability, and energy efficiency, enabling real-time optical processing for AI, image recognition, and scientific computing tasks. Its ability to perform both high-bandwidth I/O and optical tensor processing opens up new possibilities for next-generation optical computing systems.