A silicon carbide crystal smaller than a shoebox will replace room-sized atomic clocks for navigating submarines and spacecraft. The project exploits quantum defects in silicon carbide—atomic-scale gaps in the crystal lattice—that emit an ultra-pure microwave signal when hit with light. This signal serves as a frequency standard, much like the caesium or rubidium atoms in conventional atomic clocks, but without the bulky vacuum chambers and magnetic shielding those systems require. Current precision clocks, such as hydrogen MASERs, are too large and fragile for many real-world uses. They drift in accuracy when moved or exposed to radiation. The silicon carbide clock sidesteps those problems: the material is physically tough, radiation-hard, and the clock’s frequency is locked to the immutable quantum properties of the defects, not to external conditions. If the technology works, it will deliver stable timing for GPS-denied navigation, subsea operations, and satellite constellations—anywhere that needs accurate time but cannot accommodate a lab-sized instrument. The project is applied engineering, not fundamental science: it integrates existing UK-developed building blocks into a working prototype.
View original technical description
QS-EXACT, Quantum SiC for EXtreme Application Clock Technology, will integrate a series of building block technologies developed by UK industry into a robust timing system built by Nascent Semiconductor. This technology takes a new approach to the realisation of a precision clock that is highly accurate and will result in stable timing systems which are crucial to the operation of a wide range of infrastructure. There are a number of different types of atomic clock currently in operation, ranging in size, accuracy, and stability. Typical atomic clocks use microwave emissions from rubidium or caesium as a frequency standard. An example of a more accurate clock is based on the hydrogen MASER (the microwave equivalent to the LASER). However, these MASER systems are very large and unsuited to many applications. This project will exploit the quantum mechanical properties of atomic scale defects in silicon carbide, a wide bandgap semiconductor, to create a clock with a unique combination of stability, accuracy, portability and durability. The electronic structure of the silicon vacancy defect in silicon carbide results in the emission of a spectrally pure microwave signal when the defects are optically excited; allowing for the construction of a solid state silicon carbide MASER. Such an approach to crafting a clock is advantageous in a number of ways. Silicon carbide has exemplary physical properties and so such a system will be intrinsically resilient and radiation hard. The system does not suffer from stability issues that restrict the deployment of other clocks, as the frequency of the MASER is constrained by the quantum properties of the defects. The technology will offer a more compact and durable timing system that those currently available, but with a comparable performance. As a result it will be ideally suited for operations in challenging environments, from subsea to space, navigating submarines and delivering precision on-orbit operations.
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know