Nav: Home

NIST's compact atomic gyroscope displays new twists

July 11, 2019

Researchers at the National Institute of Standards and Technology (NIST) have upgraded their compact atomic gyroscope to enable multitasking measurement capabilities and measure its performance, important steps toward practical applications.

Described in a new paper, the quantum gyroscope design and evaluation processes were led by three women -- a highly unusual situation in physics and a source of pride for project leader Elizabeth Donley at NIST. Postdoctoral researchers Yun-Jhih Chen and Azure Hansen totally rebuilt the apparatus over the past couple of years.

"Not only did we build a simple quantum gyroscope, but this is the first time anyone has demonstrated simultaneous measurement of rotation, rotation angle and acceleration with a single source of atoms," Donley said. "Other gyroscopes, including the classical ones currently used in phones and planes, can measure only one axis of rotation. This is also the first time we're reporting a sensitivity for the acceleration and rotation measurements."

The NIST team previously measured rotation with an earlier version of the quantum gyroscope. The apparatus was upgraded to boost the signal strength and data acquisition speed to enable competitive sensitivity measurements. Researchers also added a pattern recognition algorithm derived from machine learning to automatically extract information from images of the atoms.

The NIST gyroscope is an atom interferometer, taking advantage of the fact that atoms can act as both particles and waves. Rotation and acceleration are deduced from images of interfering matter waves (which show the probability of a particle's position in space) from atoms in two different energy states.

Atom interferometers could be used in navigation and geodesy (the study of the shape of the Earth based on measurements of gravity) because of their sensitivity to acceleration and rotation combined with their long-term stability and accuracy. The development of small, lightweight, low-power atom interferometers is key to moving the instruments out of the laboratory to applications in the field.

The NIST team developed a simplified scheme amenable to portable applications using a single, tiny cloud of atoms that falls by only a few millimeters during the measurements. A glass chamber just 1 cubic centimeter in volume contains about 10 million cold rubidium atoms that are trapped and released.

Currently, a full-size optics table is required for the lasers, and a few racks of electronics are needed as well. The laser setup would need to be made more compact and integrated before the gyroscope could be used in the field, Donley said. Other research groups are reducing the size of these laser systems, she added.

The NIST gyroscope's sensitivities for the magnitude and direction of the rotation measurements are 0.033 degrees per second and 0.27 degrees with one second averaging time, respectively. These results are approaching the sensitivity levels achieved by other research groups using much larger atom interferometers, Donley said. Moreover, the NIST gyroscope is unique in that it can measure rotations along two axes and an acceleration along one axis simultaneously with a single source of atoms.

In the NIST gyroscope, when the atoms are first trapped in a cloud and then released to fall under gravity, a laser beam causes them to transition between two energy states. This process involves absorption and emission of light particles, which gives the atoms momentum and causes their matter waves to separate and later recombine to interfere. When the atoms speed up or rotate, their matter waves shift and interfere in predictable ways, visible in images of the expanded cloud.

The atoms are imaged by shining a second, weak laser beam through the cloud. Because atoms in different energy states absorb light of different frequencies, the images show interference bands of atom populations in the two different states. The rotation rate and rotation axis are measured by analyzing the spacing and direction of the interference bands across the atom cloud. Acceleration is measured from changes in the position of the central band. The interferometer is sensitive to acceleration along the direction of the laser beam and sensitive to rotations perpendicular to the beam.

The instrument could be used as a gyrocompass, because the atoms sense rotation in the plane tangential to the surface of Earth. The rotation signals, due to the Earth's rotation, point north, as is useful in navigation.
-end-
Paper: Y.-J . Chen, A. Hansen, G.W. Hoth, E. Ivanov, B. Pelle, J. Kitching and E.A. Donley. 2019. Multi-axis atom interferometer gyroscope with a single source of atoms. Physical Review Applied. DOI: 10.1103/PhysRevApplied.12.014019

National Institute of Standards and Technology (NIST)

Related Atoms Articles:

Stenciling with atoms in 2-dimensional materials possible
The possibilities for the new field of two-dimensional, one-atomic-layer-thick materials, including but not limited to graphene, appear almost limitless.
Microprocessors based on a layer of just 3 atoms
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics.
Super sensitive devices work on recycling atoms
Next-generation sensors to be used in fields as diverse as mineral exploration and climate change will be turbo boosted thanks to University of Queensland and University of Sussex research.
Breakthrough with a chain of gold atoms
The precise control of electron transport in microelectronics makes complex logic circuits possible that are in daily use in smartphones and laptops.
Sorting machine for atoms
Physicists at the University of Bonn have cleared a further hurdle on the path to creating quantum computers: in a recent study, they present a method with which they can very quickly and precisely sort large numbers of atoms.
Boron atoms stretch out, gain new powers
Ribbons and single-atom chains of boron would have unique physical and electronic properties, according to theoretical physicists at Rice University.
ANU demonstrates 'ghost imaging' with atoms
A team of physicists at the Australian National University have used a technique known as 'ghost imaging' to create an image of an object from atoms that never interact with it.
'Weighing' atoms with electrons
The chemical properties of atoms depend on the number of protons in their nuclei, placing them into the periodic table.
New approach to determining how atoms are arranged in materials
Researchers have developed a novel approach to characterizing how atoms are arranged in materials, using Bayesian statistical methods to glean new insights into the structure of materials.
Magnetic atoms arranged in neat rows
Physicists at Friedrich-Alexander Universität Erlangen-Nürnberg and the Vienna University of Technology have successfully created one-dimensional magnetic atom chains for the first time.

Related Atoms Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Digital Manipulation
Technology has reshaped our lives in amazing ways. But at what cost? This hour, TED speakers reveal how what we see, read, believe — even how we vote — can be manipulated by the technology we use. Guests include journalist Carole Cadwalladr, consumer advocate Finn Myrstad, writer and marketing professor Scott Galloway, behavioral designer Nir Eyal, and computer graphics researcher Doug Roble.
Now Playing: Science for the People

#530 Why Aren't We Dead Yet?
We only notice our immune systems when they aren't working properly, or when they're under attack. How does our immune system understand what bits of us are us, and what bits are invading germs and viruses? How different are human immune systems from the immune systems of other creatures? And is the immune system so often the target of sketchy medical advice? Those questions and more, this week in our conversation with author Idan Ben-Barak about his book "Why Aren't We Dead Yet?: The Survivor’s Guide to the Immune System".