Nov 28, 2023 06:59 PM
https://www.quantamagazine.org/meet-stra...-20231127/
INTRO: After a year of trial and error, Liyang Chen had managed to whittle down a metallic wire into a microscopic strand half the width of an E.coli bacterium — just thin enough to allow a trickle of electric current to pass through. The drips of that current might, Chen hoped, help settle a persistent mystery about how charge moves through a bewildering class of materials known as strange metals.
Chen, then a graduate student, and his collaborators at Rice University measured the current flowing through their atoms-thin strand of metal. And they found that it flowed smoothly and evenly. So evenly, in fact, that it defied physicists’ standard conception of electricity in metals.
Canonically, electric current results from the collective movement of electrons, each carrying one indivisible chunk of electric charge. But the dead steadiness of Chen’s current implied that it wasn’t made of units at all. It was like finding a liquid that somehow lacked individually recognizable molecules.
While that might sound outlandish, it’s exactly what some physicists expected from the metal the group tested, which along with its unusual kin has beguiled and bewildered physicists since the 1980s. “It’s a very beautiful piece of work,” said Subir Sachdev, a theoretical physicist at Harvard University who specializes in strange metals.
The observation, reported last week in the journal Science, is one of the most straightforward indications yet that whatever carries current through these unusual metals doesn’t look anything like electrons. The new experiment strengthens suspicions that a new quantum phenomenon is arising within strange metals. It also provides new grist for theoretical physicists attempting to understand what it might be... (MORE - missing details)
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And yet it's been known for ages that electrons themselves move slower through a conductor than the electromagnetic effects.
INTRO: After a year of trial and error, Liyang Chen had managed to whittle down a metallic wire into a microscopic strand half the width of an E.coli bacterium — just thin enough to allow a trickle of electric current to pass through. The drips of that current might, Chen hoped, help settle a persistent mystery about how charge moves through a bewildering class of materials known as strange metals.
Chen, then a graduate student, and his collaborators at Rice University measured the current flowing through their atoms-thin strand of metal. And they found that it flowed smoothly and evenly. So evenly, in fact, that it defied physicists’ standard conception of electricity in metals.
Canonically, electric current results from the collective movement of electrons, each carrying one indivisible chunk of electric charge. But the dead steadiness of Chen’s current implied that it wasn’t made of units at all. It was like finding a liquid that somehow lacked individually recognizable molecules.
While that might sound outlandish, it’s exactly what some physicists expected from the metal the group tested, which along with its unusual kin has beguiled and bewildered physicists since the 1980s. “It’s a very beautiful piece of work,” said Subir Sachdev, a theoretical physicist at Harvard University who specializes in strange metals.
The observation, reported last week in the journal Science, is one of the most straightforward indications yet that whatever carries current through these unusual metals doesn’t look anything like electrons. The new experiment strengthens suspicions that a new quantum phenomenon is arising within strange metals. It also provides new grist for theoretical physicists attempting to understand what it might be... (MORE - missing details)
- - - - - - - - - - -
And yet it's been known for ages that electrons themselves move slower through a conductor than the electromagnetic effects.