Artist's impression of quantum Entanglement. Scientists created a quantum entanglement crystal that could detect extremely weak electromagnetic fields by combining the spins of berylliumions and their motions.
Researchers have created a beryllium-based crystal that can detect extremely weak electromagnetic fields by using a peculiarity of quantum mechanics. This work could be used one day to detect dark matter particles, called axions.
Researchers created the quantum crystal by trapping 150 charged particles of beryllium or ions using an array of electrodes and magnetic field that helped them overcome their natural attraction for one another, Ana Maria Rey (an atomic physicist at JILA), a joint institute of the National Institute of Standards and Technology and University of Colorado Boulder told Live Science.
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Rey and her coworkers trapped the ions using their system of electrodes and fields. The atoms formed a flat sheet twice the thickness of a human hair when they were trapped. The resulting crystal-like structure resembled a crystal, which vibrates when it is disturbed by an outside force.
Rey stated, "When you excite atoms they don't move separately." They move together."
The beryllium crystal moved when it encountered an electromagnetic field. This movement could be used to measure the strength of the field.
However, measurements of quantum mechanical systems are limited by the Heisenberg uncertainty principle. This states that certain properties, such as position and momentum of a particle cannot be simultaneously known with high precision.
The team found a way around this limitation using entanglement, which is where quantum particles' attributes are intrinsically linked together.
Rey stated, "By using Entanglement, it's possible to sense things that aren’t possible otherwise."
She and her colleagues created a web that entangled the spins of the beryllium-ions motions. Quantum systems look like tiny tops, and spin is the direction that these tops point.
The crystal would vibrate if it moved a certain amount. Rey stated that the uncertainty principle means that any measurement of this displacement or the amount of ions moving would be subjected to precision limits.
She said that to measure displacement, we need a displacement greater than the quantum noise.
The noise from the ions' spins and motions is reduced by the interaction between them. This allows the researchers to measure tiny fluctuations in the crystal. The researchers tested the system by passing a weak electromagnetic signal through it, and it vibrated. Science published the article Aug. 6 about their work.
The crystal detects tiny electromagnetic signals 10 times better than any previous quantum sensors. The team believes that they can create a more sensitive detector capable to searching for axions by adding more berylliumions.
Axions, a proposed ultralight dark matter particle, are one millionth to a billionth of the mass of an electron. A few models of the axion show that it might be capable of sometimes converting i n into a photon, which would make it no longer dark and produce weak electromagnetic fields. If any axions were to fly through a laboratory containing this beryllium-crystal crystal, it might pick up their presence.
Live Science spoke out about the "immense experiment" and the beautiful results it produced. Daniel Carney, a theoretical physicalist at Lawrence Berkeley National Laboratory in Berkeley (California), was not involved in this research.
Carney believes that the work can be used for more than just the hunt for dark matter. He also believes it could have many other applications such as searching for defects or electromagnetic fields in a material.
Original publication on Live Science
