Scientists have spotted a long hypothesized state of matter in the laboratory for the first time.
By firing lasers at rubidium atoms, scientists have created a quantum spin liquid.
The atoms in this quantum magnetic soup quickly became connected, linking up their states across the entire material in a process called quantum entanglement. This breakthrough could pave the way for the development of even better quantum computers, as it means that any change to one atom causes immediate changes in all of the others in the material.
There are 12 stunning quantum physics experiments.
The co-director of the Harvard Quantum Initiative, a professor of physics at Harvard University, said that it was a very special moment in the field. You can really manipulate this exotic state and understand its properties. People have never been able to observe this new state of matter.
When materials are forced into disobeying the rules that govern their magnetic behavior, quantum spin liquids emerge.
The spin of electrons is a type of quantum momentum that can point either up or down. In normal magnets, the spins of neighboring electrons orient themselves until they all point in the same direction, generating a magnetic field. The spins of two neighboring electrons can flip to oppose each other in non-magnetic materials. The magnetic poles form a pattern.
The electrons refuse to choose in quantum spin liquids. Instead of sitting next to each other, the electrons are arranged into a triangular lattice so that they have two immediate neighbors. Two electrons can align their spins, but a third will always be the odd one out, creating a constantly changing of agitated electrons.
The researchers call it a "frustrated" magnet. The electrons and their atoms are thrown into a quantum superposition when the spin states no longer know which way to point. The ever-fluctuating spins now exist simultaneously as both spin up and spin down, and the constant switch causes atoms all the way across the material to entangle with each other in a complex quantum state.
The researchers created a near perfect facsimile of the ideal quantum spin liquid because they couldn't directly study it. They chilled an array of rubidium atoms, which can be used to minutely design and simulation various quantum processes, to temperatures of 10 microkelvins.
The atom can be put in a state known as a Rydberg state when one of the electrons is in a higher energy level than the others. The rules of quantum mechanics ensure that an atom doesn't want to be in a state that's similar to the one it's in. The researchers fired lasers at certain atoms in the array to mimic the three-way tug-of-war seen in a quantum spin liquid.
The researchers conducted tests on the array and confirmed that the atoms had become entangled across the entire material. They created a quantum spin liquid.
The proof of concept test is for designing qubits, or quantum bits, of a quantum computer. quantum computers use qubits, which can be used in more than one state at once, and they use bits, which are 0s and 1s. Any interaction with the outside world can destroy the information Qubits carry.
The special nature of the quantum spin liquid could allow for more robust information storage. Instead of just one qubit, it could allow for information to be contained in the shape of the entangled spin states that make up the material itself. The qubit is less likely to lose all of its information if it is formed by multiple parts.
In the future, the researchers hope to create larger, more practical qubit, but for now, they created a tiny one.
"Learning how to create and use such topological qubits would be a major step toward the realization of reliable quantum computers," co-author Giulia Semeghini, a quantum physicist at Harvard University, said in the statement. We show how to create a topological qubit, but we still need to demonstrate how you can manipulate it. There's more to be explored.
Live Science published the original article.
