Scientists at Imperial College London are developing a quantum compass that can pinpoint locations without relying on external signals like GPS. This device uses quantum mechanics and supercool atoms to achieve high accuracy, making it potentially effective in environments such as underground or underwater where traditional GPS
Background on Quantum navigation
The GPS – or, more correctly, the Global Navigation Satellite System (GNSS) – is a critical tool for the transportation industry today. Whether traveling by road, sea, or air, navigation systems help determine the exact location of vehicles and compute arrival time to destination, a feature that is critical for maintaining supply chains.
However, GNSS devices are not foolproof: GPS signals can be jammed, spoofed, or denied, leading to navigation errors. This is where quantum navigation comes in, a technology that could potentially replace GPS in the future
A quantum solution
The idea of a quantum compass is to bypass or augment current methods for pinpointing the locations of planes, cars and other objects. The aim of the Imperial College project – which has been backed by UK Research and Innovation’s Technology Missions Fund and the UK National Quantum Technologies Programme – is to create a device that is not only accurate in fixing its position, but also does not rely on receiving external signals.
What is Quantum Navigation?
Quantum navigation is like having a super-accurate, self-contained GPS inside a device. Instead of relying on signals from satellites, it uses tiny particles called atoms to figure out where it is and how it’s moving. Just think of it as a tiny internal compass that never gets lost, even in places where regular GPS doesn’t work, like underwater or in a tunnel. It’s like having a secret map built right into the device itself. This technology is still being developed, but it has the potential to be much more accurate and reliable than traditional GPS.
How does Quantum Navigation work
Quantum Sensors:
- Highly sensitive sensors are developed using quantum particles. These sensors can measure acceleration, rotation, and gravity with extreme accuracy.
- Examples of these sensors include atomic clocks and atom interferometers.
Inertial Navigation:
- The quantum sensors continuously measure the vehicle’s acceleration and rotation.
- By integrating these measurements over time, the system can calculate the vehicle’s position and velocity relative to a starting point.
Gravity Gradiometry:
- Quantum sensors can also measure variations in the Earth’s gravitational field.
- This information can be used to determine the vehicle’s altitude and position relative to the Earth’s surface.
Advantages of Quantum navigation
- Quantum navigation is ‘unjammable‘, making it more secure than GPS.
- It can be used in situations where GPS is not available, such as underwater.
- Quantum navigation can provide more accurate and reliable navigation than GPS.
Meet the protagonists: accelerometer, rubidium and lasers
At the heart of the quantum compass – which could be ready for widespread use in a few years – is a device known as an accelerometer that can measure how an object’s velocity changes over time. This information, combined with the starting point of that object, allows its future positions to be calculated.
Mobile phones and laptops possess accelerometers but these versions cannot maintain their accuracy over lengthy periods. However, quantum mechanics offers scientists a way to provide new precision and accuracy by measuring properties of supercool atoms. At extremely low temperatures, atoms behave in a “quantum” way. They act like matter and like waves. “When atoms are ultra-cold, we can use quantum mechanics to describe how they move, and this allows us to make accurate measurements that tell us how our device is changing its position,” said researchers.
The researchers are using rubidium atoms in their setup and an array of lasers to super cool them to temperatures just above absolute zero. The entire assembly is inside a vacuum chamber, and promising results were obtained when tested in laboratory conditions.
