Applications like Semiconductor fab, X-ray spectroscopy, quantum computing platforms all required ultrahigh emptiness for accuracy.
![A portable cold-atom vacuum-measurement tool [top] detects the fluorescence of roughly 1 million lithium atoms [bottom], and infers the vacuum pressure based on how quickly the fluorescence decays.](https://www.electronicsforu.com/wp-contents/uploads/2025/09/generated_image1.png)
A new atomic sensor is being developed to measure vacuum levels unlike the conventional tools. The sensor uses ultra-cold atoms as reference and can work without calibration.
Vacuum measurement is important in semiconductor fabrication, quantum computing platforms, particle and wave detections and surface analysis tools, because these systems will fail if the outside particles interfere in the process.
These technologies rely on Ultrahigh vacuum to run operation smoothly. Pressure is measured in pascals as it quantifies force over area. Normal air pressure is 100,000 Pa. Ultrahigh vacuum is below 10⁻⁷ Pa, with some processes needing 10⁻⁹ Pa. Space reaches below 10⁻²⁰ Pa, showing the ultimate limit.
With the conventional tools used today, it needs calibration as the reading depends on device geometry and gas type. A calibration means matching the tools with known pressure values, which often takes time. Also, it can release gas from heated parts in the system, disturbing the vacuum.
Atoms such as Rubidium or Lithium are cooled close to absolute zero and trapped in place using lasers and magnetic fields. Stray particles inside the particles collide with these atoms and knock some out of the trap.
By measuring how quickly the trapped atoms are knocked out, the pressure can be calculated. The calculation comes directly from the quantum sensor, so no calibration is needed, and the result stays accurate even when different gases are present.
The research is being carried out by teams at the University of British Columbia and the US National Institute of Standards and Technology. They are now testing how much further the method can go and where it can be applied in both science and industry.
