Archive for category: Main Story – Homepage

Quantum computing, though still in its early days, has the potential to dramatically increase processing power by harnessing the strange behavior of particles at the smallest scales. Some research groups have already reported performing calculations that would take a traditional supercomputer thousands of years. In the long term, quantum computers could provide unbreakable encryption and simulations of nature beyond today’s capabilities.

A UCLA-led interdisciplinary research team including collaborators at Harvard University has now developed a fundamentally new strategy for building these computers. While the current state of the art employs circuits, semiconductors and other tools of electrical engineering, the team has produced a game plan based in chemists’ ability to custom-design atomic building blocks that control the properties of larger molecular structures when they’re put together.

The findings, published last week in Nature Chemistry, could ultimately lead to a leap in quantum processing power.

“The idea is, instead of building a quantum computer, to let chemistry build it for us,” said Eric Hudson, UCLA’s David S. Saxon Presidential Professor of Physics and corresponding author of the study. “All of us are still learning the rules for this type of quantum technology, so this work is very sci-fi right now.”

Image of Eric Hudson in his UCLA office. | Stuart Wolpert/UCLA

The basic units of information in traditional computing are bits, which are each limited to one of only two values. In contrast, a group of quantum bits — or qubits — can have a vastly wider range of values, exponentially increasing a computer’s processing power. More than 1,000 normal bits are required to represent just 10 qubits, while 20 qubits require more than 1 million bits.

That characteristic, at the heart of quantum computing’s transformational potential, depends on the counterintuitive rules that apply when atoms interact. For instance, when two particles interact, they can become linked, or entangled, so that measuring the properties of one determines the properties of the other. Entangling qubits is a requirement of quantum computing.

However, this entanglement is fragile. When qubits encounter subtle variations in their environments, they lose their “quantumness,” which is needed to implement quantum algorithms. This limits the most powerful quantum computers to fewer than 100 qubits, and keeping these qubits in a quantum state requires large pieces of machinery.

To apply quantum computing practically, engineers must scale up that processing power. Hudson and his colleagues believe they have made a first step with the study, where theory guided the team to tailor-make molecules that protect quantum behavior.

The scientists developed small molecules that include calcium and oxygen atoms and act as qubits. These calcium-oxygen structures form what chemists call a functional group, meaning that it can be plugged into almost any other molecule while also conferring its own properties to that molecule.

The team showed that their functional groups maintained their desired structure even when attached to much larger molecules. Their qubits can also stand up to laser cooling, a key requirement for quantum computing.

“If we can bond a quantum functional group to a surface or some long molecule, we might be able to control more qubits,” Hudson said. “It should also be cheaper to scale up, because an atom is one of the cheapest things in the universe. You can make as many as you want.”

In addition to its potential for next-generation computing, the quantum functional group could be a boon for basic discovery in chemistry and the life sciences, for instance by helping scientists uncover more about the structure and function of various molecules and chemicals in the human body.

“Qubits can also be exquisitely sensitive tools for measurement,” said study co-author Justin Caram, a UCLA assistant professor of chemistry and biochemistry. “If we could protect them so they can survive in complex environments such as biological systems, we would be armed with so much new information about our world.”

Hudson said that the development of a chemically based quantum computer could realistically take decades and is not certain to succeed. Future steps include anchoring qubits to larger molecules, coaxing tethered qubits to interact as processors without unwanted signaling, and entangling them so that they work as a system.

The project was seeded by a Department of Energy grant that gave the physicists and chemists the chance to cut through discipline-specific jargon and speak in a common scientific language. Caram also credits UCLA’s atmosphere of easy collaboration.

“This is one of the most intellectually fulfilling projects I’ve ever worked on,” he said. “Eric and I first met having lunch at the Faculty Center. This was born out of fun conversations and being open to talking to new people.”

UCLA postdoctoral researcher Guo-Zhu Zhu is the study’s first author. Other UCLA co-authors are doctoral students Claire Dickerson and Guanming Lao and faculty members Anastassia Alexandrova and Wesley Campbell.

The study was also supported by the National Science Foundation, the Army Research Office and the Air Force Office of Scientific Research.

This article originally appeared in the UCLA Newsroom. For more news and updates from the UCLA College, visit college.ucla.edu/news.

Regardless of race, ethnicity and even political party preference, two separate UCLA-led surveys reveal that majorities of people in each group support access to legal abortion in the United States.

Recent large-scale surveys of voters and non-voters by UCLA political scientists Lorrie Frasure, Matt Barreto, Lynn Vavreck and Chris Tausanovitch took a pulse on a variety of policy issues, including abortion. These separate findings support previous research and literature that shows broad support for legal abortion.

Data from The Democracy Fund + UCLA Nationscape Project, led by Vavreck and Tausanovitch show broad support for abortion across political party lines. Nationscape was a weekly survey fielded from July 2019 through January 2021, reaching nearly 500,000 voters and non-voters representative of the U.S. adult population.

Most Democrats and Republicans — as well as independents — said they do not think abortion should be outlawed completely.

And, according to Nationscape data, most also agreed that abortion should not be limited only to instances of rape, incest or threat to the life of the mother.

Despite the two major political parties’ platforms generally taking opposing positions on abortion — Democrats support, Republicans oppose — there are people aligned with the Republican party who support legal abortion and people aligned with the Democratic party who oppose abortion. But for these cross-positioned voters, it’s important to note that abortion is not their biggest priority, Vavreck said.

Nationscape researchers know this because of a unique approach they employed to test what matters most to the electorate, essentially forcing survey respondents to make choices based on groupings of hot-button topics. The survey included 44 different policy statements and 8 hypothetical attributes of political candidates. A set of these statements were randomized into two groups of options. Survey respondents were asked to choose which group most aligned with their priorities.

For example, a Democrat who opposes legal abortion might be faced with two groupings of policy statements — one that included limiting or ending abortion. But, if the other group of policy statements held items that were more important to that person, like not deporting undocumented immigrants, they would select that option. The same held true the other way for Republicans who support legal abortion. If the other bucket of topics included things they cared more about than abortion, that was their choice.

“This happens on other issues beside abortion too, and what this tells us is that these voters and potential voters are not cross-pressured within their party. They’re not torn. They just have other priorities — they are cross-positioned, but not cross-pressured,” Vavreck said. “These surveys demonstrate that vast majorities support keeping abortion legal but that doesn’t necessarily mean that this issue is going to be pivotal to their vote choice.”

The fourth and largest installment of the Collaborative Multiracial Post-Election Survey, or CMPS, led by Frasure and Barreto, alongside Janelle Wong from University of Maryland, College Park, and Edward Vargas from Arizona State University, asked several questions about abortion, reporting results based on the race of respondents.

This survey is conducted after every presidential election, and its questions are drafted by a broad consortium of race and ethnicity politics scholars from across the United States. In 2020, the CMPS was offered in 10 languages to nearly 15,000 respondents.

CMPS data, by way of several questions, show broad support for abortion across four self-reported racial groups — Asian, Black, Latino and white.

Overall, majorities from all groups reported they either support legal abortion or are neutral on the issue, with broad margins of support across all racial and ethnic groups.

“Although the CMPS data was collected before news of the Supreme Court leak, it nonetheless reaffirms what decades of public opinion research has found —across every racial and ethnic group, Americans support safe and legal access to abortion,” said Barreto, who added that there are very low rates of opposition to abortion rights for women.

“The CMPS study makes clear that among Black, Latino, Asian and White Americans alike, there remains strong support for maintaining the protections of Roe v. Wade,” Barreto said.

When asked if limiting abortion was a specific priority for their racial community, most respondents said that it was a low priority.

This article originally appeared in the UCLA Newsroom. For more news and updates from the UCLA College, visit college.ucla.edu/news.