in the world In the field of quantum physics, it seems that another record has just been broken. in a paper Listed on the ArXiv preprint site, researchers from the University of Science and Technology of China claim to have observed atoms in a state of quantum superposition for 23 minutes. They argue that being able to keep quantum states stable for so long could help make quantum devices more durable and uncover strange new effects in quantum physics.
Superposition is a phenomenon in which an object at a given time has the potential to occupy multiple different states, but the actual state of the object is unknown. Very small objects, such as photons or electrons, demonstrate this behavior; they behave like waves, potentially occupying a variety of positions at any given time, rather than like particles with a singular position. Fundamentally, when an object is observed in superposition, its condition collapses and it is seen in only one of its potential states. You can think of this like flipping a coin: as it spins in the air, it can potentially be heads or tails at the same time, but when you look at it after it has landed, it can be just one or the other.
You may also have heard of the explanation of superposition using the famous Schrödinger’s cat paradox. This was a thought experiment proposed by physicist Erwin Schrödinger, in which a cat is placed in a sealed box with a radioactive material that will randomly decay and, when it does, kill the cat. Until the box is opened, the experiment proposes that the cat is in superposition, being simultaneously alive and dead. Although commonly used to explain superposition, Schrödinger’s experiment was intended to show the seemingly absurdity of this quantum behavior.
For years, researchers have been able to detect tiny objects that exhibit superposition, and in the laboratory light particles and even tiny crystals have been shown to occupy multiple states at the same time. But the objects in these experiments were always very unstable and their exposure to superposition extremely fleeting. However, in the new study, Chinese researchers, led by physicist Zheng-Tian Lu, appear to have used atoms trapped in light to support the phenomenon.
The researchers used about 10,000 ytterbium atoms, which they cooled to a few thousandths of a degree above absolute zero and trapped them with the electromagnetic forces of laser light. Under these conditions, the quantum states of atoms could be controlled very precisely, and the researchers took advantage of this by placing each atom in a superposition of two concurrent states that had two very different spins.
Typically, perturbations to the atoms’ environment would cause them to collapse into a single state within seconds or milliseconds, but the researchers were able to fine-tune the lasers to sustain them for an unprecedented duration of 1,400 seconds, or 23 minutes. It is important to note, however, that the work has not yet been formally independently reviewed.
Because it extends the superposition for so long, this technique, if proven possible, could be used in the future to detect and study magnetic forces, test new and exotic effects in physics, or even enable very stable quantum computer memory. . .
This story originally appeared on WIRING Italy and has been translated from Italian.