For over a hundred years, students have been taught that magnetism appears in just two forms. In the first, called ferromagnetism, all the tiny magnetic moments inside a material point the same way, as they do in an ordinary fridge magnet. In the second, antiferromagnetism, they point in opposite directions and cancel each other out, so the material shows no magnetic force at all. Now a team of physicists has won a major international physics prize for showing that this simple picture is incomplete.
The newly confirmed form is called altermagnetism. In an altermagnetic material, neighbouring magnetic moments still point in opposite directions, as in an antiferromagnet. The difference is that the surrounding crystal structure is rotated slightly, so the two sets of moments are not identical mirror images. This hidden imbalance gives the material surprising properties: it behaves like a magnet in some experiments yet stays invisible to others.
The idea was first predicted by theoretical physicists only a few years ago, and many experts treated it as a curiosity. Since then, however, research groups in several countries have produced convincing experimental evidence, using advanced imaging techniques to map the magnetic order inside these crystals. The prize committee described the work as a rare example of a prediction turning into a measurable reality within a single decade.
Why does it matter? Ordinary magnets are widely used in computer memory and electric motors, but they are difficult to control at extremely small scales. Antiferromagnets are fast and stable, yet almost impossible to read. Altermagnets appear to combine the strengths of both, which makes them attractive for the next generation of electronic devices, where information could be stored and moved with far less energy.
Researchers stress that commercial products are still years away, and that many engineering problems remain to be solved. Even so, the discovery has already changed how physicists think about a force that surrounds us every day. As one member of the team put it, we have not found a new substance; we have found a new way for matter to behave.
| 单词 | 英文释义 | 例句 |
|---|---|---|
| cancel out/ˌkænsəl ˈaʊt/ phrasal v. | to stop something from having any effect by balancing it with an opposite force | In an antiferromagnet, the two sets of magnetic moments cancel out, so the material shows no magnetic force. |
| incomplete/ˌɪnkəmˈpliːt/ adj. | not having all the parts; not whole or finished | The new discovery showed that the traditional picture of magnetism was incomplete. |
| neighbouring/ˈneɪbərɪŋ/ adj. | next to or very near something | Neighbouring magnetic moments inside the crystal point in opposite directions. |
| imbalance/ɪmˈbæləns/ n. | a situation in which two things are not equal or not in the right amounts | This hidden imbalance gives the material a set of surprising properties. |
| curiosity/ˌkjʊəriˈɒsəti/ n. | something unusual that people find interesting but not very important | At first, many experts treated the new idea as a scientific curiosity. |
| convincing/kənˈvɪnsɪŋ/ adj. | making you believe that something is true | Several laboratories have produced convincing evidence for the new form of magnetism. |
| evidence/ˈevɪdəns/ n. | facts or signs that show something is true | The team collected evidence by using advanced imaging techniques. |
| stable/ˈsteɪbl/ adj. | not likely to change, move or break; steady | Antiferromagnets are fast and stable, but almost impossible to read. |
| combine/kəmˈbaɪn/ v. | to have two or more different things or qualities together | Altermagnets appear to combine the strengths of two other kinds of magnet. |
| commercial/kəˈmɜːʃl/ adj. | connected with buying and selling goods, especially for profit | The researchers admit that commercial products are still years away. |
| surround/səˈraʊnd/ v. | to be all around something or someone | Magnetism is a force that surrounds us every day. |
Dear Mr Bennett,
I am writing to suggest an idea for the science club's programme next term.
I recently came across an article about a group of physicists who have won a major prize for discovering a third form of magnetism.
I found the evidence surprisingly convincing, and it seems this hidden force could change the way computers are built in the future.
I was wondering whether it would be possible to invite a guest speaker from the university.
I believe this would be of great benefit to students, as many of us are preparing for courses in science or engineering.
A talk like this would also be useful for members who are simply curious about new technology, because the speaker could explain the subject in simple language.
Please let me know if there is anything I can do to help, such as contacting the department or designing a poster for the event.
Thank you for considering my suggestion, and I look forward to hearing from you.
Yours sincerely, Li Hua (170 words)