{"id":442905,"date":"2026-02-01T14:07:14","date_gmt":"2026-02-01T14:07:14","guid":{"rendered":"https:\/\/www.newsbeep.com\/us\/442905\/"},"modified":"2026-02-01T14:07:14","modified_gmt":"2026-02-01T14:07:14","slug":"scientists-discover-quantum-particles-remember-past-states","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us\/442905\/","title":{"rendered":"Scientists discover quantum particles remember past states"},"content":{"rendered":"

Researchers have tracked a looping fractional charge<\/a> in ultrathin carbon and seen it return with a consistent interference rhythm.<\/p>\n

The result strengthens the case for quantum particles whose collective state can retain a record of earlier exchanges.<\/p>\n

A loop with consequences
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That rhythmic signal came from a gate-defined loop reported in a recent paper, where resistance rose and fell predictably.<\/p>\n

By keeping the device stable, Dr. Yuval Ronen, a condensed matter physicist, tested whether the looped charge stayed coherent.<\/p>\n

His laboratory at the Weizmann Institute of Science (WIS<\/a>) builds graphene circuits that let scientists steer quantum motion with electrodes.<\/p>\n

Such steering matters because future quantum computers need information that survives local bumps, not just perfect isolation in a freezer.<\/p>\n

When electrons become fractions<\/p>\n

Extreme cold and intense magnetic fields can force electrons to organize into new patterns that carry charge in pieces.<\/p>\n

The fractional quantum Hall effect<\/a>, electrons behaving as smaller charges along edges, was first reported in 1982.<\/p>\n

Physicists often call these fraction-like excitations anyons, particle-like bundles that appear only in two dimensions.<\/p>\n

Even-denominator fractions are strong candidates for non-Abelian anyons, swaps that reshape a shared quantum state, rather than simple timing changes.<\/p>\n

Reading quantum interference<\/p>\n

Quantum particles<\/a> also act as waves. A wave function, the math that tracks those possibilities, describes their state.<\/p>\n

When the loop split a wave and later recombined it, the two paths either reinforced or canceled, changing resistance.<\/p>\n

The Aharonov-Bohm effect<\/a>, a timing offset caused by encircling magnetic flux, set the rhythm for resistance bands.<\/p>\n

Because the pattern stayed coherent over many circuits, the signal carried clues about what kind of fractional charge traveled.<\/p>\n

The half-charge surprise<\/p>\n

One report captured the team\u2019s turning point, when the interference closely matched an even-denominator fraction.<\/p>\n

\u201cIn our experiment, we managed to measure a fractional electron<\/a> with an even denominator,\u201d said Ronen.<\/p>\n

Instead of the expected one-quarter charge, the orbiting wave looked like half an electron, hinting at a paired traveler.<\/p>\n

Ronen\u2019s team linked that half-charge signal to two particles moving together, but they had not separated them.<\/p>\n

Inside the charged island<\/p>\n

Changing voltages on the device also let the researchers tune electron density inside the island that the loop enclosed.<\/p>\n

As that density changed, interference lines tilted, implying that the trapped particles carried one-quarter of an electron\u2019s charge.<\/p>\n

Those internal charges interacted with the circling wave<\/a>, and their presence altered the recombination timing that set resistance.<\/p>\n

By matching that island charge with the earlier loop result, the evidence leaned toward non-Abelian behavior.<\/p>\n

Memory stored in topology<\/p>\n

Order matters for these particles because each swap can rewrite the system-wide topological pattern, protected by global structure rather than microscopic details.<\/p>\n

\u201cIn non-Abelian anyons, the exchange of positions leaves an imprint on the shape of the wave function,\u201d explains Ronen.<\/p>\n

A classic review<\/a> describes how a whole system can store exchange history without pinning information to one spot.<\/p>\n

That nonlocal storage sets a high bar for stray defects or vibrations to erase the encoded order.<\/p>\n

Why noise matters less<\/p>\n

Most quantum<\/a> computers build qubits, units of information in a quantum computer, from local states that readily drift.<\/p>\n

Heat, stray fields, and tiny material defects can nudge those local states, which scrambles the stored information.<\/p>\n

\u201cIn non-Abelian anyons, information about the order of exchanges is stored not locally but in the wave function of the entire system,\u201d adds Ronen.<\/p>\n

If experiments like this one can control those exchanges on demand, error correction may become simpler and less expensive.<\/p>\n

What evidence still lacks<\/p>\n

Interference patterns alone cannot prove a full non-Abelian identity, because several quantum states can mimic similar timing.<\/p>\n

The main data fit either a half-charge circling once or a one-quarter charge looping twice before recombining.<\/p>\n

Temperature effects and fluctuations inside the island can also blur the clearest signatures, especially when multiple particles interact.<\/p>\n

Only a direct readout of exchange order, not just charge size, will settle whether the system truly remembers.<\/p>\n

Next steps for braiding<\/p>\n

Work at WIS now focuses on isolating the smallest charges and controlling how many sit inside the island.<\/p>\n

\u201cWe\u2019ve shown that bilayer graphene almost certainly hosts particles that are non-Abelian anyons,\u201d concludes Ronen.<\/p>\n

To test the promised memory, the team needs to swap particles in different orders and compare the system-wide wave function.<\/p>\n

If those ordered swaps leave distinct interference signatures, engineers could start designing logic elements that resist local noise.<\/p>\n

A cautious path forward<\/p>\n

This bilayer graphene device kept its signal coherent long enough to hint at particles with both fractional charge and history.<\/p>\n

Progress now depends on isolating single non-Abelian anyons. Researchers must also prove that their exchange order changes the whole system as predicted.<\/p>\n

The study is published in Nature<\/a>.<\/p>\n

\u2014\u2013<\/p>\n

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\u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"Researchers have tracked a looping fractional charge in ultrathin carbon and seen it return with a consistent interference…\n","protected":false},"author":2,"featured_media":442906,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[49],"tags":[199,79],"class_list":{"0":"post-442905","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physics","8":"tag-physics","9":"tag-science"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/442905","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=442905"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/442905\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/442906"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=442905"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=442905"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=442905"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}