GPS is an integral part of modern technology, from portable GPS locators to in-car navigation to drones, that it’s hard to imagine a life without it. However, there are a number of situations where GPS is unavailable, due to factors like tall buildings which block the satellite signals that GPS relies on. In other cases, GPS signals can be deliberately blocked, preventing it from functioning correctly.
An alternative form of navigation is needed for everything from navigating large vehicles to looking for dark matter in the far-flung corners of space. Now, researchers at Imperial College London have invented a quantum “the compass” that allows navigation without reliance on satellites. The instrument which is technically called a “standalone quantum accelerometer,” is tiny enough to be transportable and was shown off recently at the National Quantum Technologies Showcase.
An accelerometer is a tool that’s used to measure the changes in an object’s velocity over time and is a common piece of technology that you most likely have embedded in your phone. With information about the original location of an object and information about its velocity, location can be determined. However, the problem with basic accelerometers is that their accuracy becomes poorer over time without an external reference to recalibrate them. This means they are useless for jobs where exact location specificity is required such as navigation.
The newly developed quantum accelerometer has a very high level of accuracy. It’s achieved by measuring the movements of supercool atoms, which are cooled to such a degree that they display quantum behavior, they are both particles and waves. The wave properties of the atoms are affected by acceleration, so the scientists monitor the movements of the atoms by creating an atom interferometer: a tool that measures the displacement of waves. This means that the accelerometer is capable of measuring movement through space in a highly accurate way.
The device is still too large to fit into a compact space, but it’s appropriate for use on ships and trains which require to be precisely located when GPS might not be available. Its large size is due to the powerful lasers that are needed to get the atoms cold enough for the accelerometer to work.