Turnkey System to Laser-cool and Trap Strontium Atoms for Quantum Technology Applications


Infocomm - Quantum Computing


Laser-cooled and trapped strontium is an important candidate for applications in quantum sensing and metrology, quantum computing, and quantum simulations of complex systems. Usually, the production of cold samples of strontium in a magneto-optical trap (MOT) involves a bulky setup that requires a significant investment in resources, time and expertise to assemble and maintain.

This technology offer is a compact turnkey MOT device which requires less maintenance, and relies on a simpler atomic source for strontium, which is based on thermal ablation of pure strontium by a high-power focused laser beam.  A proof-of-principle has been obtained for the thermal ablation source, trapping cold strontium atoms in a MOT directly from the strontium vapour released during the ablation process.

The technology owner is planning to develop a prototype of the turnkey cold strontium setup, and believes that this would be of interest to potential technology collaborators such as researchers and companies working on quantum technologies. The technology owner is keen to out-license this technology, as well as explore technology co-development, including with potential collaborators with other application ideas.


The main innovation of this turnkey MOT system is a laser-controlled thermal ablation source for cold strontium. Conventionally the strontium source is an oven, which has to be heated at 500-600 ⁰C to produce an atomic beam. The hot atomic beam then undergoes a few additional stages of pre-cooling before the atoms can be trapped in a MOT. Due to the high temperature of the oven, proper heat management is also required.

Instead of an oven, this technology uses a focused high-power ablation laser (10-100 W) to locally heat a small spot (typically a few micrometres in diameter) on a pure strontium target.  The thermal ablation source has the advantage of not requiring any heat management and is more compact compared to the conventional oven source.

Due to the small ablation spot, a high rate of heating releases the strontium vapour within 50ms for direct loading into the MOT. As soon as the ablation laser is turned off, the ablation spot cools down and the emission of the strontium vapour stops. The remaining strontium in the vapour adsorbs rapidly on the walls of the vacuum chamber, reducing the background pressure for a longer MOT trapping lifetime.

In terms of performance, the technology owner has demonstrated a loading rate of at least 1×10-6 atoms/s, leading to 4.5 million strontium atoms in the MOT. A lifetime of 4.7s in the MOT has been achieved, which is long enough for the user to perform complex manipulations and operations of the cold atoms.


The main application of this turnkey MOT system is in the field of quantum technologies. This compact design will be suitable for portable and high precision quantum sensing and metrology devices. Some examples include gravitational field sensors for geodesy and mineral search applications, accelerometers, and optical clocks. It would also be of interest in the development of quantum computing and simulation platforms.

Furthermore, the thermal ablation source is a universal technique that can be applied to laser-cool and trap other atomic elements like ytterbium, dysprosium, erbium and transition metals. This should interest a broader community of researchers in cold atomic physics.

The market for this technology consists of researchers in the field of cold atoms and companies working in the line of quantum technologies. While the market size is small currently, it is expected to grow rapidly due to the increase investments globally in developing quantum technologies. In Singapore, the Quantum Engineering Programme was launched to further develop quantum technologies. Over 100 million dollars have been committed into this programme so far. Overseas initiatives like the Quantum Flagship ( > 1 billion Euros) and the National Quantum Initiative (1.2 billion USD) have also been launched in the past 3 years to kick-start and accelerate the quantum technology industry.


  • Offers savings on cost, time and manpower to set up and maintain a system to laser-cool and trap strontium. User can focus on the applications of the cold atoms.
  • Emission of strontium is controllable, occurring only during ablation process, which leads to more efficient use of the source.
  • Turnkey operation. Cooling and trapping beam paths will be pre-aligned and optimized, and the user only needs to provide the laser through a fibre. Minimal tuning and alignment is required from the user.  Easily integrates with existing laser system of users.