Quantum 'compass' to replace GPS navigation
Yet, you should not expect one in your mobile phone any time soonEuropost , London
GPS is such an essential part of modern technology, from portable GPS locators to in-car navigation to drones, that it’s hard to imagine life without it. However, there are a number of situations where GPS is not available, due to factors like tall buildings which block the satellite signals GPS relies on. In other cases, GPS signals can be deliberately blocked or jammed, preventing it from working correctly and making it useless. Thus, a group of scientists at Imperial College London have come up with an alternative form of navigation, technically called a “standalone quantum accelerometer,” that can navigate almost everything from large vehicles to searching for dark matter in the far flung corners of space, without reliance on satellites.
The accelerometer itself isn't a new instrument and is actually a common piece of technology that you likely have embedded in your phone. With information about the original position of an object and information about its velocity, location can be determined. However, the problem with basic accelerometers is that their accuracy becomes poor over time without an external reference to recalibrate them. This means they are not useful for jobs where exact location specificity is required such as navigation.
The newly developed quantum accelerometer, whose prototype system shown off this week in London, however, has a very high level of accuracy. It achieves this 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. Since the wave properties of the atoms are effected by acceleration, the scientists examine the movements of the atoms by creating an atom interferometer — a tool which measures the displacement of waves. The result is an extremely sensitive device that's also considerably more reliable than conventional accelerometers as it can measure movement through space in a highly accurate way.
The device, on the downside, is still too large to fit into a compact space, because of the powerful lasers that are required to get the atoms cold enough for the accelerometer to work. Yet, with its about three-feet width and height it is truly ready for ships, trains and other large vehicles where size and power requirements aren't major factors. The researchers also expect the underlying concepts to help with science studies, such as looking for gravitational waves.