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Originally published by Oak Ridge National Laboratory.

A team led by the Department of Energy’s Oak Ridge National Laboratory has found a rare quantum material in which electrons move in coordinated ways, essentially “dancing.” Straining the material creates an electronic band structure that sets the stage for exotic, more tightly correlated behavior — akin to tangoing — among Dirac electrons, which are especially mobile electric charge carriers that may someday enable faster transistors. The results are published in the journal Science Advances.

“We combined correlation and topology in one system,” said co-principal investigator Jong Mok Ok, who conceived the study with principal investigator Ho Nyung Lee of ORNL. Topology probes properties that are preserved even when a geometric object undergoes deformation, such as when it is stretched or squeezed. “The research could prove indispensable for future information and computing technologies,” added Ok, a former ORNL postdoctoral fellow.

In conventional materials, electrons move predictably (for example, lethargically in insulators or energetically in metals). In quantum materials in which electrons strongly interact with each other, physical forces cause the electrons to behave in unexpected but correlated ways; one electron’s movement forces nearby electrons to respond.

To study this tight tango in topological quantum materials, Ok led the synthesis of an extremely stable crystalline thin film of a transition metal oxide. He and colleagues made the film using pulsed-laser epitaxy and strained it to compress the layers and stabilize a phase that does not exist in the bulk crystal. The scientists were the first to stabilize this phase.

Using theory-based simulations, co-principal investigator Narayan Mohanta, a former ORNL postdoctoral fellow, predicted the band structure of the strained material. “In the strained environment, the compound that we investigated, strontium niobate, a perovskite oxide, changes its structure, creating a special symmetry with a new electron band structure,” Mohanta said.

Different states of a quantum mechanical system are called “degenerate” if they have the same energy value upon measurement. Electrons are equally likely to fill each degenerate state. In this case, the special symmetry results in four states occurring in a single energy level.

“Because of the special symmetry, the degeneracy is protected,” Mohanta said. “The Dirac electron dispersion that we found here is new in a material.” He performed calculations with Satoshi Okamoto, who developed a model for discovering how crystal symmetry influences band structure.

“Think of a quantum material under a magnetic field as a 10-story building with residents on each floor,” Ok posited. “Each floor is a defined, quantized energy level. Increasing the field strength is akin to pulling a fire alarm that drives all the residents down to the ground floor to meet at a safe place. In reality, it drives all the Dirac electrons to a ground energy level called the extreme quantum limit.”

Lee added, “Confined here, the electrons crowd together. Their interactions increase dramatically, and their behavior becomes interconnected and complicated.” This correlated electron behavior, a departure from a single-particle picture, sets the stage for unexpected behavior, such as electron entanglement. In entanglement, a state Einstein called “spooky action at a distance,” multiple objects behave as one. It is key to realizing quantum computing.

“Our goal is to understand what will happen when electrons enter the extreme quantum limit, where we find phenomena we still don’t understand,” Lee said. “This is a mysterious area.”

Speedy Dirac electrons hold promise in materials including graphene, topological insulators and certain unconventional superconductors. ORNL’s unique material is a Dirac semimetal, in which electron valence and conduction bands cross and this topology yields surprising behavior. Ok led measurements of the Dirac semimetal’s strong electron correlations.

“We found the highest electron mobility in oxide-based systems,” Ok said. “This is the first oxide-based Dirac material reaching the extreme quantum limit.”

That bodes well for advanced electronics. Theory predicts that it should take about 100,000 tesla (a unit of magnetic measurement) for electrons in conventional semiconductors to reach the extreme quantum limit. The researchers took their strain-engineered topological quantum material to Eun Sang Choi of the National High Magnetic Field Laboratory at the University of Florida to see what it would take to drive electrons to the extreme quantum limit. There, he measured quantum oscillations showing the material would require only 3 tesla to achieve that.

Other specialized facilities allowed the scientists to experimentally confirm the behavior Mohanta predicted. The experiments occurred at low temperatures so that electrons could move around without getting bumped by atomic-lattice vibrations. Jeremy Levy’s group at the University of Pittsburgh and the Pittsburgh Quantum Institute confirmed quantum transport properties. With synchrotron x-ray diffraction, Hua Zhou at the Advanced Photon Source, a DOE Office of Science user facility at Argonne National Laboratory, confirmed that the material’s crystallographic structure stabilized in the thin film phase yielded the unique Dirac band structure. Sangmoon Yoon and Andrew Lupini, both of ORNL, conducted scanning transmission electron microscopy experiments at ORNL that showed that the epitaxially grown thin films had sharp interfaces between layers and that the transport behaviors were intrinsic to strained strontium niobate.

“Until now, we could not fully explore the physics of the extreme quantum limit due to the difficulties in pushing all electrons to one energy level to see what would happen,” Lee said. “Now, we can push all the electrons to this extreme quantum limit by applying only a few tesla of magnetic field in a lab, accelerating our understanding of quantum entanglement.”

The title of the Science Advances paper is “Correlated Oxide Dirac Semimetal in the Extreme Quantum Limit.”

The DOE Office of Science supported the research. High magnetic field measurements were performed at the National High Magnetic Field Laboratory, which is supported by the National Science Foundation and the state of Florida. The research used resources of the Advanced Photon Source, a DOE Office of Science user facility at Argonne National Laboratory; its extraordinary facility operations to provide beam time during the pandemic were supported in part by the DOE Office of Science through the National Virtual Biotechnology Laboratory, a consortium of DOE national laboratories focused on the response to COVID-19, with funding provided by the Coronavirus CARES Act.

UT-Battelle manages ORNL for the Department of Energy’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.

 

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SunZia Wind’s massive 2.4 GW project hits a big milestone

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SunZia Wind’s massive 2.4 GW project hits a big milestone

GE Vernova has produced over half the turbines needed for SunZia Wind, which will be the largest wind farm in the Western Hemisphere when it comes online in 2026.

GE Vernova has manufactured enough turbines at its Pensacola, Florida, factory to supply over 1.2 gigawatts (GW) of the turbines needed for the $5 billion, 2.4 GW SunZia Wind, a project milestone. The wind farm will be sited in Lincoln, Torrance, and San Miguel counties in New Mexico.

At a ribbon-cutting event for Pensacola’s new customer experience center, GE Vernova CEO Scott Strazik noted that since 2023, the company has invested around $70 million in the Pensacola factory.

The Pensacola investments are part of the announcement GE Vernova made in January that it will invest nearly $600 million in its US factories and facilities over the next two years to help meet the surging electricity demands globally. GE Vernova says it’s expecting its investments to create more than 1,500 new US jobs.

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Vic Abate, CEO of GE Vernova Wind, said, “Our dedicated employees in Pensacola are working to address increasing energy demands for the US. The workhorse turbines manufactured at this world-class factory are engineered for reliability and scalability, ensuring our customers can meet growing energy demand.”

SunZia Wind and Transmission will create US history’s largest clean energy infrastructure project.

Read more: The largest clean energy project in US history closes $11B, starts full construction


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Stablecoin issuer Circle files for IPO as public markets open to crypto

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USDC stablecoin issuer Circle files for IPO as public markets open to crypto

Jeremy Allaire, Co-Founder and CEO, Circle 

David A. Grogan | CNBC

Circle, the company behind the USDC stablecoin, has filed for an initial public offering and plans to list on the New York Stock Exchange.

The prospectus, filed with the SEC on Tuesday, lays the groundwork for Circle’s long-anticipated entry into the public markets.

JPMorgan Chase and Citigroup are serving as lead underwriters, and the company is reportedly aiming for a valuation of up to $5 billion. It will trade under ticker symbol CRCL.

It marks Circle’s second attempt at going public. A prior merger with a special purpose acquisition company (SPAC) collapsed in late 2022 amid regulatory challenges. Since then, Circle has made strategic moves to position itself closer to the heart of global finance, including the announcement last year that it would relocate its headquarters from Boston to One World Trade Center in New York.

Circle reported $1.68 billion in revenue and reserve income in 2024, up from $1.45 billion in 2023 and $772 million in 2022. The company reported net income last year of about $156 million., down from $268 million a year earlier.

Read more about tech and crypto from CNBC Pro

A successful IPO would make Circle one of the most prominent pure-play crypto companies to list on a U.S. exchange. Coinbase went public through a direct listing in 2021 and has a market cap of about $44 billion.

Circle will be trying to hit the public markets at a volatile moment for tech stocks, with the Nasdaq having just wrapped up its steepest quarterly drop since 2022. The tech IPO market has been mostly dry for over three years, though there are signs of life. Online lender Klarna, digital health company Hinge Health and ticketing marketplace StubHub have all filed their prospectuses recently. Late last week, artificial intelligence infrastructure provider CoreWeave held the biggest IPO for a U.S. venture-backed tech company since 2021. But the company scaled back the offering and the stock had a disappointing first two days of trading before rebounding on Tuesday.

Circle is best known as the issuer of USD Coin (USDC), the world’s second-largest stablecoin by market capitalization.

Pegged one-to-one to the U.S. dollar and backed by cash and short-term Treasury securities, USDC has roughly $60 billion in circulation and makes up about 26% of the total market cap for stablecoins, behind Tether‘s 67% dominance. Its market cap has grown 36% this year, however, compared with Tether’s 5% growth.

The company’s push into public markets reflects a broader moment for the crypto industry, which is enjoying political favor under a more crypto-friendly U.S. administration. The stablecoin sector specifically has been ramping up as the industry gains confidence that the crypto market will get its first piece of U.S. legislation passed and implemented this year, focusing on stablecoins. President Donald Trump has said he hopes lawmakers will send stablecoin legislation to his desk before Congress’s August recess.

Stablecoins’ growth could have investment implications for crypto exchanges like Robinhood and Coinbase as they become a bigger part of crypto trading and cross-border transfers. Coinbase also has an agreement with Circle to share 50% of the revenue of its USDC stablecoin, and Coinbase CEO Brian Armstrong said on the company’s most recent earnings call that it has a “stretch goal to make USDC the number 1 stablecoin.” 

The stablecoin market has grown about 11% so far this year and about 47% in the past year, and has become a “systemically important” part of the crypto market, according to Bernstein. Historically, digital assets in this sector have been used for trading and as collateral in decentralized finance (DeFi), and crypto investors watch them closely for evidence of demand, liquidity and activity in the market.

WATCH: Circle CEO on launching first stablecoin in Japan

Circle CEO on launching the first stablecoin in Japan

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BYD’s global EV takeover is far from over as overseas sales double to start 2025

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BYD's global EV takeover is far from over as overseas sales double to start 2025

After its meteoric rise in the global auto industry last year, the Chinese EV giant is off to a hot start in 2025. BYD sold over one million EVs and plug-in hybrids in the first three months of the year. Even more impressive, BYD’s overseas sales doubled to start the year as it expands into new markets. With new EVs arriving, some predict BYD could see even more growth this year.

BYD’s overseas sales are surging as new EVs arrive

BYD sold 377,420 new energy vehicles (NEVs) last month alone. Like most Chinese automakers, BYD reports NEV sales, including plug-in hybrids (PHEVs) and fully electric vehicles (EVs).

Of the 371,419 passenger vehicles BYD sold in March, 166,109 were EVs, and the other 205,310 were PHEVs. Combined, BYD’s sales were up 23% compared to last year.

BYD’s Dynasty and Ocean series accounted for 350,615, while its luxury Denza brand sold 12,620, Fang Cheng Bao had 8,051, and its ultra-luxury Yangwang brand sold another 133 models.

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Through the first three months of 2025, BYD sold over one million (1,000,804) NEVs. That’s up 60% from the 626,263 sold in Q1 2024. Fully electric models accounted for 416,388 while PHEV sales reached 569,710, an increase of 39% and 76% from last year, respectively.

BYD-overseas-EV-sales
BYD Dolphin (left) and Atto 3 (right) at the 2024 Tokyo Spring Festival (Source: BYD Japan)

BYD’s overseas sales reached a new record last month, with 72,723 vehicles sold in markets outside of China. Through March, BYD has sold over 206,000 NEVs overseas, more than double (+110%) the number it sold last year.

BYD has made a name for itself with ultra-low-cost EVs like the Seagull, which starts at under $10,000 in China. In overseas markets, like Mexico, it’s sold as the Dolphin Mini and starts at around 358,800 pesos, or around $20,000.

BYD-overseas-EV-sales
BYD Seagull EV (Dolphin Mini) testing in Brazil (Source: BYD)

The world’s largest EV maker is quickly expanding into new segments with pickup trucks, smart SUVs, luxury models, and electric supercars rolling out.

Last week, BYD launched the Yangwang U7, its first ultra-luxury electric sedan. With four electric motors, the U7 packs 1,287 horsepower, good for a 0 to 62 mph (0 to 100 km/h) sprint in just 2.9 seconds. It also has up to 720 km (447 miles) CLTC driving range.

BYD's-ultra-luxury-EV-sedan
BYD Yangwang U7 ultra-luxury electric sedan (Source: Yangwang)

The Porsche Panamera-size EV is loaded with BYD’s top-tier “God’s Eye” A advanced driving assistance system, DiPilot 600, and a host of other premium features. All of that, and it starts at just just 628,000 yuan ($87,700).

In Europe, BYD is aggressively expanding with new vehicles tailored to buyers in the region, like the Sealion 7 midsize SUV and Atto 2. It’s also expected to launch the low-cost Seagull EV in Europe later this year or early 2026 as the “Dolphin Surf.”

BYD-overseas-EV-sales
BYD’s wide-reaching electric vehicle portfolio (Source: BYD)

According to S&P Global Mobility, BYD’s sales are expected to double in Europe this year to around 186,000. By 2029, that number could reach 400,000 or more.

BYD outsold Honda and Nissan in 2024. As it aims to sell 5.5 million vehicles this year, BYD could be on track to surpass Ford in global sales this year. BYD also aims to sell over 800,000 EVs overseas in 2025, double the number it sold last year.

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