The 91探花 is proud to announce that 56 faculty and researchers who completed their work while at 91探花have been named on the list from Clarivate.

The annual list identifies researchers who demonstrated significant influence in their chosen field or fields through the publication of multiple highly cited papers during the last decade. Their names are drawn from the publications that rank in the top 1% by citations for field and publication year in the .

Highly Cited Researchers demonstrate significant and broad influence in their fields of research. The total list includes 7,131 awards from more than 1,300 institutions in 60 countries and regions. This small fraction of the global researcher population contributes disproportionately to extending the frontiers of knowledge and contributing to innovations that make the world healthier, more sustainable and which drive societal impact, according to Clarivate.

The that determines the 鈥渨ho鈥檚 who鈥� of influential researchers is drawn from data and analysis performed by bibliometric experts and data scientists at the Institute for Scientific Information at Clarivate.

The list below includes faculty and researchers whose primary affiliation is with the UW, Fred Hutch Cancer Center, and the Institute for Health Metrics and Evaluation.

Please note: Some of the people on the list are no longer with the 91探花and their current affiliation is noted. This list reflects initial data from Clarivate and may be updated.

Ivan Anishchenko (Vilya)

David Baker

William A. Banks

Gregory N. Bratman

Steven L. Brunton

Guozhong Cao

Ting Cao

Lauren Carter (Gates Medical Research Institute)

Helen Chu

David H. Cobden

Katharine H. D. Crawford

Riza M. Daza

Frank DiMaio

Kristie L. Ebi

Evan E. Eichler

Emmanuela Gakidou

David Ginger

Raphael Gottardo (CHUV)

Alexander L. Greninger

Simon I. Hay

Andrew Hill (Infinimmune)

Eric Huang

Michael C. Jensen (BrainChild)

Neil P.聽 King

C. Dirk Keene

J. Nathan Kutz

Eric H. Larson

Aaron Lyon

Michael J. MacCoss

Brendan MacLean

C. M. Marcus

Julian D. Marshall

Ali Mokdad

Thomas J. Montine (Stanford)

Mohsen Naghavi

Marian L. Neuhouser

Julian D. Olden

Robert W. Palmatier

David Pigott

Hannah A. Pliner (Bristol Myers Squibb)

Ganesh Raghu

Stanley Riddell

Andrea Schietinger (Memorial Sloan Kettering Cancer Center)

Jay Shendure

M. Alejandra Tortorici

Troy R. Torgerson (Allen Institute)

Cole Trapnell

Katherine R. Tuttle

David Veesler

Theo Vos

Alexandra C. Walls (BioNTech SE)

Bryan J. Weiner

Di Xiao

Jie Xiao

Xiaodong Xu

Jihui Yang

The 91探花 is proud to announce that more than 40 faculty and researchers who completed their work while at 91探花have been named on the annual list from Clarivate.

The annual list identifies researchers who demonstrated significant influence in their chosen field or fields through the publication of multiple highly cited papers during the last decade. Their names are drawn from the publications that rank in the top 1% by citations for field and publication year in the Web of Science citation index.

The list of faculty and researchers whose primary affiliation is with the 91探花or with the Institute for Health Metrics and Evaluation who were acknowledged for their work includes:

David Baker

William A. Banks

Gregory N. Bratman

Steven L. Brunton

Guozhong Cao

William A. Catterall

Helen Chu

David H. Cobden

Katharine H.D. Crawford

Riza M. Daza

Frank DiMaio

Evan E. Eichler

Michael Gale Jr.

Raphael Gottardo

Allison J. Greaney

Alexander L. Greninger

Simon I. Hay

Celestia S. Higano

Neil P. King

James B. Leverenz

Charles M. Marcus

Philip Mease

Ali Mokdad

Thomas J. Montine*

Christopher J. L. Murray

Mohsen Naghavi

William S. Noble

Young-Jun Park

David M. Pigott

Stanley Riddell

Andrea Schietinger **

Jay Shendure

M. Alejandra Tortorici

Troy R. Torgerson***

Cole Trapnell

David Veesler

Theo Vos

Alexandra C. Walls****

Bryan J. Weiner

Spencer A. Wood

Sanfeng Wu

Di Xiao

Xiaodong Xu

The that determines the 鈥渨ho鈥檚 who鈥� of influential researchers draws on the data and analysis performed by bibliometric experts and data scientists at the Institute for Scientific Information at Clarivate. It also uses the tallies to identify the countries and research institutions where these scientific elite are based.

The full 2023 Highly Cited Researchers list and executive summary can be found online .

* now is at Stanford University.

** now is at Memorial Sloan Kettering Cancer Center.

*** now is at the Allen Institute.

**** now is at BoiNTech SE.

now is at Princeton University.

The 91探花 is proud to announce that 47 faculty and researchers who completed their work while at 91探花have been named on the annual list from Clarivate.

The highly anticipated annual list identifies researchers who demonstrated significant influence in their chosen field or fields through the publication of multiple highly cited papers during the last decade. Their names are drawn from the publications that rank in the top 1% by citations for field and publication year in the Web of Science citation index.

The list of faculty and researchers who were acknowledged for their work while at 91探花includes:

• David Baker
• Frank DiMaio
• William Sheffler
• Dr. Jay Shendure
• Cole Trapnell
• David Veesler
• Alexandra C. Walls*
• Philip Mease
• Dr. Christopher J. L. Murray
• Dr. Ganesh Raghu
• Dr. Stanley Riddell
• Alejandra Tortorici
• Dr. William A. Banks
• Gregory N. Bratman
• Steven L. Brunton
• Guozhong Cao
• William A. Catterall
• David H. Cobden
• Riza M. Daza
• Dr. E. Patchen Dellinger
• Dr. Janet A. Englund
• E. Erskine
• Michael Gale Jr.
• Raphael Gottardo
• Celestia S. Higano
• Neil P. King
• Ali Mokdad
• William S. Noble
• Julian D. Olden
• L. Patrick
• David L. Smith
• Dr. Piper Meigs Treuting
• Spencer A. Wood
• Jesse R. Zaneveld
• Ning Zheng
• Dr. Hans D. Ochs
• Simon I. Hay
• Evan E. Eichler
• Deborah A. Nickerson**
• John A. Stamatoyannopoulos***
• Dr. Thomas J. Montine****
• Di Xiao
• Xiaodong Xu
• Bryan J. Weiner
• Mohsen Naghavi
• Theo Vos
• David M. Pigott

The that determines the 鈥渨ho鈥檚 who鈥� of influential researchers draws on the data and analysis performed by bibliometric experts and data scientists at the Institute for Scientific Information at Clarivate. It also uses the tallies to identify the countries and research institutions where these scientific elite are based. This year Clarivate partnered with Retraction Watch and extended the qualitative analysis of the Highly Cited Researchers list, addressing increasing concerns over potential misconduct.

The full 2022 Highly Cited Researchers list and executive summary can be found online .

* now is at BioNTech SE.

** on Dec. 24, 2021.

*** now is at Altius.

**** now is at Stanford University.

Scientists have visualized the electronic structure in a microelectronic device for the first time, opening up opportunities for finely tuned, high-performance electronic devices.

Physicists from the 91探花 and the University of Warwick developed a technique to measure the energy and momentum of electrons in operating microelectronic devices made of atomically thin 鈥� so-called 2D 鈥� materials.

Using this information, the researchers created visual representations of the electrical and optical properties of the materials to guide engineers in maximizing 2D materials’ potential in electronic components.

The , published July 17 in the journal , could also pave the way for the types of 2D semiconductors that are likely to play a role in the next generation of electronics, in applications such as photovoltaics, mobile devices and quantum computers.

The electronic structure of a material describes how electrons behave within that material, and therefore the nature of the current flowing through it. That behavior varies depending upon the voltage 鈥� the amount of “pressure” on its electrons 鈥� applied to the material, and so changes to the electronic structure with voltage determine the efficiency of microelectronic circuits.

These changes in electronic structure in operating devices are what underpin all of modern electronics. But until now there has been no way to directly see these changes to help us understand how they affect the behavior of electrons.

Their technique used angle-resolved photoemission spectroscopy, or ARPES, to “excite” electrons in the chosen material.

“It used to be that the only way to learn about what the electrons are doing in an operating semiconductor device was to compare its current-voltage characteristics with complicated models,” said co-corresponding author , a 91探花 professor of physics and faculty member in both the 聽and the . “Now, thanks to recent advances, which allow the ARPES technique to be applied to tiny spots, combined with the advent of two-dimensional materials where the electronic action can be right on the very surface, we can directly measure the electronic spectrum in detail and see how it changes in real time.”

By applying this technique, scientists will have the information they need to develop “fine-tuned” electronic components that work more efficiently and operate at high performance with lower power consumption. It will also help in the development of 2D semiconductors that are seen as potential components for the next generation of electronics, with applications in flexible electronics, photovoltaics and spintronics. Unlike today’s 3D semiconductors, 2D semiconductors consist of just a few layers of atoms.

“How the electronic structure changes with voltage is what determines how a transistor in your computer or television works,” said co-corresponding author , an associate professor of physics at the University of Warwick. “For the first time we are directly visualising those changes. Not being able to see how [structure] changes with voltages was a big missing link. This work is at the fundamental level and is a big step in understanding materials and the science behind them.”

By focusing a beam of ultraviolet or x-ray light on atoms in a localized area, the excited electrons are knocked out of their atoms. Scientists can then measure the energy and direction of travel of the electrons, which 鈥� thanks to laws for the conservation of energy and momentum 鈥� allows them to work out the energy and momentum they had within the material. That determines the electronic structure of the material, which can then be compared against theoretical predictions based on state-of-the-art electronic structure calculations performed by co-author ‘s group at the University of Warwick.

“This powerful spectroscopy technique will open new opportunities to study fundamental phenomena, such as visualization of electrically tunable topological phase transition and聽 doping effects on correlated electronic phases, which are otherwise challenging,” said co-corresponding author , a 91探花 professor of both physics and materials science and engineering, as well as faculty member in the .

The team first tested the technique using graphene before applying it to 2D transition metal dichalcogenide, or TMD, semiconductors.

“The new insight into the materials has helped us to understand the band gaps of these semiconductors, which is the most important parameter that affects their behavior, from what wavelength of light they emit, to how they switch current in a transistor,” said Wilson.

The measurements were taken at the at the , in collaboration with co-author .

“This changes the game,” said Cobden.

Lead author is Paul Nguyen, a 91探花 doctoral student in the Department of Physics. Co-authors are Nathan Wilson and Joshua Kahn, both 91探花 doctoral students in the Department of Physics; Natalie Teutsch and Xue Xia with the University of Warwick Department of Physics; Viktor Kandyba with the Elettra – Sincrotrone Trieste; and Gabriel Constantinescu with the University of Cambridge. The research was funded by the U.S. Department of Energy, the U.K. Engineering and Physical Sciences Research Council, the National Science Foundation, the University of Warwick, the Winton Programme for the Physics of Sustainability, the Cambridge Trust European Scholarship and the University of Cambridge.

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Adapted from by Peter Thorley at the University of Warwick.

These can be prepared in crystalline sheets as thin as a single monolayer, only one or a few atoms thick. Within a monolayer, electrons are restricted in how they can move: Like pieces on a board game, they can move front to back, side to side or diagonally 鈥� but not up or down聽This constraint makes monolayers functionally two-dimensional.

The 2-D realm exposes properties predicted by quantum mechanics 鈥� the probability-wave-based rules that underlie the behavior of all matter. Since 鈥� the first monolayer 鈥� debuted in 2004, scientists have isolated many other 2-D materials and shown that they harbor unique physical and chemical properties that could revolutionize computing and telecommunications, among other fields.

For a team led by scientists at the 91探花, the 2-D form of one metallic compound 鈥� tungsten ditelluride, or WTe₂ 鈥� is a bevy of quantum revelations. In a published online July 23 in the journal , researchers report their latest discovery about WTe₂: Its 2-D form can undergo “ferroelectric switching.” They found that when two monolayers are combined, the resulting “bilayer” develops a spontaneous electrical polarization. This polarization can be flipped between two opposite states by an applied electric field.

“Finding ferroelectric switching in this 2-D material was a complete surprise,” said senior author , a 91探花professor of physics. “We weren’t looking for it, but we saw odd behavior, and after making a hypothesis about its nature we designed some experiments that confirmed it nicely.”

Materials with ferroelectric properties can have applications in memory storage, capacitors, RFID card technologies and even medical sensors.

“Think of ferroelectrics as nature’s switch,” said Cobden. “The polarized state of the ferroelectric material means that you have an uneven distribution of charges within the material 鈥� and when the ferroelectric switching occurs, the charges move collectively, rather as they would in an artificial electronic switch based on transistors.”

The 91探花team created WTe₂ monolayers from its the 3-D crystalline form, which was grown by co-authors at Oak Ridge National Laboratory and Zhiying Zhao at the University of Tennessee, Knoxville. Then the 91探花team, working in an oxygen-free isolation box to prevent WTe₂ from degrading, used Scotch Tape to exfoliate thin sheets of WTe₂ from the crystal 鈥� a technique widely used to isolate graphene and other 2-D materials. With these sheets isolated, they could measure their physical and chemical properties, which led to the discovery of the ferroelectric characteristics.

WTe₂ is the first exfoliated 2-D material known to undergo ferroelectric switching. Before this discovery, scientists had only seen ferroelectric switching in . 聽But WTe₂ isn’t an electrical insulator; it is actually a metal, albeit not a very good one. WTe₂ also maintains the ferroelectric switching at room temperature, and its switching is reliable and doesn’t degrade over time, unlike many conventional 3-D ferroelectric materials, according to Cobden. These characteristics may make WTe₂ a promising material for smaller, more robust technological applications than other ferroelectric compounds.

“The unique combination of physical characteristics we saw in WTe₂ is a reminder that all sorts of new phenomena can be observed in 2-D materials,” said Cobden.

Ferroelectric switching is the second major discovery Cobden and his team have made about monolayer WTe₂. In a 2017 in , the team reported that this material is also a “topological insulator,” the first 2-D material with this exotic property.

In a topological insulator, the electrons’ 鈥� mathematical summaries of their quantum mechanical states 鈥� have a kind of built-in twist. Thanks to the difficulty of removing this twist, topological insulators could have applications in quantum computing 鈥� a field that seeks to exploit the quantum-mechanical properties of electrons, atoms or crystals to generate computing power that is exponentially faster than today’s technology. The 91探花team’s discovery also stemmed from theories developed by , a 91探花professor emeritus of physics who in part for his work on topology in the 2-D realm.

Cobden and his colleagues plan to keep exploring monolayer WTe₂ to see what else they can learn.

“Everything we have measured so far about WTe₂ has some surprise in it,” said Cobden. “It’s exciting to think what we might find next.”

91探花faculty co-author is , a professor of both physics and materials science and engineering, as well as a faculty member with the UW’s . Co-lead authors are postdoctoral researcher Zaiyao Fei, doctoral student Wenjin Zhao and research scientist Tauno Palomaki 鈥� all in the 91探花Department of Physics. Additional co-authors are physics doctoral student Bosong Sun and , a former research intern. The research was funded by the United States Department of Energy, the National Science Foundation and the Air Force Office of Scientific Research.

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For more information, contact Cobden at 206-543-2686 or cobden@uw.edu.

Grant numbers: DE-SC0002197, DE-SC0018171, DMR-1420451, EFRI 2DARE 1433496, MRSEC 1719797, FA9550-14-1-0277.

Physicists at the 91探花 have conducted the most precise and controlled measurements yet of the interaction between the atoms and molecules that comprise air and the type of carbon surface used in battery electrodes and air filters 鈥� key information for improving those technologies.

A team led by , 91探花professor of physics, used a carbon nanotube 鈥� a seamless, hollow graphite structure a million times thinner than a drinking straw 鈥� acting as a transistor to study what happens when gas atoms come into contact with the nanotube’s surface. Their findings were in May in the journal Nature Physics.

Cobden said he and co-authors found that when an atom or molecule sticks to the nanotube a tiny fraction of the charge of one electron is transferred to its surface, resulting in a measurable change in electrical resistance.

“This aspect of atoms interacting with surfaces has never been detected unambiguously before,” Cobden said. “When many atoms are stuck to the miniscule tube at the same time, the measurements reveal their collective dances, including big fluctuations that occur on warming analogous to the boiling of water.”

Lithium batteries involve lithium atoms sticking and transferring charges to carbon electrodes, and in activated charcoal filters, molecules stick to the carbon surface to be removed, Cobden explained.

“Various forms of carbon, including nanotubes, are considered for hydrogen or other fuel storage because they have a huge internal surface area for the fuel molecules to stick to. However, these technological situations are extremely complex and difficult to do precise, clear-cut measurements on.”

This work, he said, resulted in the most precise and controlled measurements of these interactions ever made, “and will allow scientists to learn new things about the interplay of atoms and molecules with a carbon surface,” important for improving technologies including batteries, electrodes and air filters.

Co-authors were , professor emeritus of physics, doctoral students and research associate , all of the UW. The research was funded by the National Science Foundation.

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For more information, contact Cobden at 206-543-2686 or cobden@uw.edu. Grant number: DMR 1206208. Image is available .

The 91探花 researchers have demonstrated that two of these single-layer semiconductor materials can be connected in an atomically seamless fashion known as a . This result could be the basis for next-generation flexible and transparent computing, better light-emitting diodes, or LEDs, and solar technologies.

“Heterojunctions are fundamental elements of electronic and photonic devices,” said senior author , a 91探花assistant professor of materials science and engineering and of physics. “Our experimental demonstration of such junctions between two-dimensional materials should enable new kinds of transistors, LEDs, nanolasers, and solar cells to be developed for highly integrated electronic and optical circuits within a single atomic plane.”

The online this week in .

The researchers discovered that two flat semiconductor materials can be connected edge-to-edge with crystalline perfection. They worked with two single-layer, or monolayer, materials 鈥� molybdenum diselenide and tungsten diselenide 鈥� that have very similar structures, which was key to creating the composite two-dimensional semiconductor.

Collaborators from the electron microscopy center at the in England found that all the atoms in both materials formed a single honeycomb lattice structure, without any distortions or discontinuities. This provides the strongest possible link between two single-layer materials, necessary for flexible devices. Within the same family of materials it is feasible that researchers could bond other pairs together in the same way.

The researchers created the junctions in a small furnace at the UW. First, they inserted a powder mixture of the two materials into a chamber heated to 900 degrees Celsius (1,652 F). Hydrogen gas was then passed through the chamber and the evaporated atoms from one of the materials were carried toward a cooler region of the tube and deposited as single-layer crystals in the shape of triangles.

After a while, evaporated atoms from the second material then attached to the edges of the triangle to create a seamless semiconducting heterojunction.

“This is a scalable technique,” said Sanfeng Wu, a 91探花doctoral student in physics and one of the lead authors. “Because the materials have different properties, they evaporate and separate at different times automatically. The second material forms around the first triangle that just previously formed. That’s why these lattices are so beautifully connected.”

With a larger furnace, it would be possible to mass-produce sheets of these semiconductor heterostructures, the researchers said. On a small scale, it takes about five minutes to grow the crystals, with up to two hours of heating and cooling time.

“We are very excited about the new science and engineering opportunities provided by these novel structures,” said senior author , a 91探花professor of physics. “In the future, combinations of two-dimensional materials may be integrated together in this way to form all kinds of interesting electronic structures such as in-plane quantum wells and quantum wires, superlattices, fully functioning transistors, and even complete electronic circuits.”

The researchers have already demonstrated that the junction interacts with light much more strongly than the rest of the monolayer, which is encouraging for optoelectric and photonic applications like solar cells.

Other co-authors are Chunming Huang and Pasqual Rivera of 91探花physics; Ana Sanchez, Richard Beanland and Jonathan Peters at the University of Warwick; Jason Ross of 91探花materials science and engineering; and Wang Yao, a theoretical physicist of the University of Hong Kong.

This research was funded by the U.S. Department of Energy, the UW’s , the Research Grant Council of Hong Kong, the University Grants Committee of Hong Kong, the Croucher Foundation, the Science City Research Alliance and the Higher Education Funding Council for England’s Strategic Development Fund.

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For more information, contact Wu at swu02@uw.edu.

Grant numbers: U.S. Department of Energy, Basic Energy Sciences, Materials Sciences and Engineering Division (DE-SC0008145) (DE-SC0002197).

Also well known is that the solid form of many materials can have numerous phases, but it is difficult to pinpoint the temperature and pressure for the points at which three solid phases can coexist stably.

Scientists now have made the first-ever accurate determination of a solid-state triple point in a substance called vanadium dioxide, which is known for switching rapidly 鈥� in as little as one 10-trillionth of a second 鈥� from an electrical insulator to a conductor, and thus could be useful in various technologies.

“These solid-state triple points are fiendishly difficult to study, essentially because聽 the different shapes of the solid phases makes it hard for them to match up happily at their interfaces,” said David Cobden, a 91探花 physics professor.

“There are, in theory, many triple points hidden inside a solid, but they are very rarely probed.”

Cobden is the lead author of a paper describing the work, published Aug. 22 in Nature.

In 1959, researchers at Bell Laboratories discovered vanadium dioxide’s ability to rearrange electrons and shift from an insulator to a conductor, called a metal-insulator transition. Twenty years later it was discovered that there are two slightly different insulating phases.

The new research shows that those two insulating phases and the conducting phase in solid vanadium dioxide can coexist stably at 65 degrees Celsius, give or take a tenth of a degree (65 degrees C is equal to 149 degrees Fahrenheit).

To find that triple point, Cobden’s team stretched vanadium dioxide nanowires under a microscope. The team had to build an apparatus to stretch the tiny wires without breaking them, and it was the stretching that allowed the observation of the triple point, Cobden said.

It turned out that when the material manifested its triple point, no force was being applied 鈥� the wires were not being stretched or compressed.

The researchers originally set out simply to learn more about the phase transition and only gradually realized that the triple point was key to it, Cobden said. That process took several years, and then it took a couple more to design an experiment to pin down the triple point.

“No previous experiment was able to investigate the properties around the triple point,” he said.

He regards the work as “just a step, but a significant step” in understanding the metal-insulator transition in vanadium dioxide. That could lead to development of new types of electrical and optical switches, Cobden said, and similar experiments could lead to breakthroughs with other materials.

“If you don’t know the triple point, you don’t know the basic facts about this phase transition,” he said. “You will never be able to make use of the transition unless you understand it better.”

Co-authors are 91探花physics graduate students Jae Hyung Park, T. Serkan Kasirga and Zaiyao Fei; undergraduates Jim Coy and Scott Hunter; and postdoctoral researcher Chunming Huang. The work was funded by the U.S. Department of Energy.

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For more information, contact Cobden at 206-543-2686 or cobden@uw.edu.