Fusion Diagnostics

Controlled-fusion diagnostic systems monitor plasma parameters (temperature, density, magnetic field and more) in real time — they are the irreplaceable "eyes" that make steady-state operation and burn control of a fusion reactor possible. The company delivers complete diagnostic solutions spanning from core components to full systems.

THz Interferometer

A fusion reaction must reach hundreds of millions of degrees Celsius, at which the gas is fully ionized into a high-temperature plasma. As of 2025, the tokamak route accounts for roughly 50% of the world's fusion devices, and its core metric is the fusion triple product — the product of plasma density, temperature and energy confinement time. The company's terahertz interferometers are used mainly to monitor plasma density; everything from the terahertz laser, detectors and optical path to system integration is developed and manufactured in-house.

Independently Developed Core Components

The generation and detection of terahertz waves is the technological cornerstone of fusion plasma diagnostics. Drawing on years of expertise from the CAS Institute of Plasma Physics, and through long-standing collaborative R&D with the China Academy of Engineering Physics and the CAS Suzhou Institute of Nano-Tech and Nano-Bionics, the company develops and mass-produces a range of core components — terahertz lasers, detectors and solid-state multiplier sources — that both support full-system integration and are sold independently to universities and research institutes.

Diagnostic System Integration & Long-term O&M

Because fusion devices remain in the engineering-experiment stage, each device differs significantly in structural dimensions, magnetic-field topology, vacuum environment, operating parameters and diagnostic interfaces. Every diagnostic system the company provides is custom-designed for the specific device; the company also takes on turnkey contracts for core diagnostics and provides long-term operation-and-maintenance service across the device's full operating lifecycle.

THz Polarimeter-Interferometer

The terahertz polarimeter-interferometer exploits the Faraday rotation and Cotton-Mouton effect experienced by the polarization state of terahertz waves as they propagate through a magnetized plasma, allowing simultaneous measurement of plasma density and the internal current (magnetic field) distribution. It provides key data for tokamak current-profile reconstruction and magnetohydrodynamic stability studies. (Detailed technical materials in preparation.)

CO₂ Dispersion Interferometer

The CO₂ dispersion interferometer uses a common-path, two-color scheme combining a long-wavelength laser and its frequency-doubled short-wavelength beam. By measuring the phase difference between the two beams caused by plasma dispersion, it retrieves the line-integrated electron density while effectively suppressing mechanical vibration and optical-path disturbances — well suited to real-time density feedback control on long-pulse, high-density steady-state devices. (Detailed technical materials in preparation.)

Alpha-Particle Diagnostics

Alpha-particle diagnostics target burning fusion plasmas. By detecting the energy spectrum and spatial distribution of the high-energy alpha particles produced by deuterium-tritium fusion reactions, they assess the confinement, slowing-down and self-heating effect of these particles on the plasma — an important means for burning-plasma physics research and fusion power-gain evaluation. (Detailed technical materials in preparation.)