Tag Archive for physics

Morgan Appointed Honorary Professor at Queen’s University

Foss Professor of Physics Thomas J. Morgan

Tom Morgan

Foss Professor of Physics Thomas Morgan has been appointed as honorary professor at Queen’s University in Belfast, Northern Ireland. He will hold this title for the next three years.

Morgan was recognized for this honor for his broad research contributions to the fields of atomic and molecular physics and plasma physics. He has published over 90 research papers, including many with international collaborators from Germany, France, Mexico and Japan.

Morgan will continue his research work at Wesleyan on highly excited states of diatomic molecules, and, as an honorary professor title holder, he will have access to Queen’s University’s resources for his research in the area of low temperature plasma physics. The appointment provides him an opportunity to concentrate on specific research projects in this area with collaborators at Queen’s University.

Local Children Learn about Physics from Wesleyan Faculty, Students

Christina Othon, assistant professor of physics, assistant professor of integrative sciences, met with students enrolled in the Green Street Teaching and Learning Center‘s Discovery AfterSchool Program on Dec. 1. Othon and Wesleyan students Danielle Levinson ’19, Alexis Braunrot ’18 and and graduate student Stefan Kramel taught the AfterSchool attendees about physics through hands-on activities.

GSTLC s a community-based studio that develops, applies, and disseminates best practices in experiential teaching and learning which enhance Wesleyan and the greater community. The Discovery AfterSchool Programs offers a range of classes in the arts, sciences and math for children in Grades 1- 5.

The objective for the day was to investigate the properties of matter, to review the states of matter, and to discuss some of the ways we can change the properties of matter. Othon’s expertise is in soft matter, and therefore the group focused on fluids, gels and plastic deformation. After reviewing how to define the properties of a liquid, students were asked about how they would characterize some unusual materials like peanut butter or Jell-O.

“Of course these are materials which hold their shape, similar to a solid, but deform under stress or strain like a fluid. We therefore determined that the categories of liquid, gas and solid are not rigid categories, but that some materials have properties of both,” Othon said. “We then conducted some experiments on viscosity where students made predictions about which fluids would flow most quickly down an incline plane. The fluids were water, oil, chocolate sauce, honey and ketchup. The students observed that the ketchup behaved differently than all of the other fluids, and that the clumping of the ketchup dramatically impacted how fast it flowed.”

After investigating viscosity, the group discussed how to change the properties of materials. The students recognized that through temperature they could change water to a solid.

To demonstrate the change in structural properties, Othon and the students decided to make bouncy balls through chemical crosslinking. The students took two fluid solutions (glue and starch, and a salt solution in water), and mixed them to make their own bouncy balls.

“This is a messy project, but is highly engaging and the students greatly enjoyed it,” Othon said. “We always have a lot of fun working with the children at Green Street. We hope that this experience helps makes studying science exciting, and that they realize they can make observations of everyday objects and phenomena in their home.”

(Photos by Rebecca Goldfarb Terry ’19)

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Chemistry, Physics Students Attend Biomedical Research Conference

Contributed photo

From Nov. 9-12, two faculty members and five students from the physics and chemistry departments, attended the Annual Biomedical Research Conference for Minority Students in Tampa, Fla.

Candice Etson, assistant professor of physics, and Erika Taylor, associate professor of chemistry, were joined by McNair Scholars Luz Mendez ’17, Tatianna Pryce ’17, Stacy Uchendu ’17 and Hanna Morales ’17; and Wesleyan Mathematics and Science (WesMaSS) Scholar Helen Karimi ’19.

Students observed other research being performed around the nation by students who are members of underrepresented groups in Science, Technology, Engineering and Mathematics (STEM). In addition, the Wesleyan students presented their own research and Morales and Karimi were awarded Outstanding Poster Presentation Awards.

“Through the PIE Initiative, Wesleyan has a deliberate strategy to support underrepresented students and faculty in STEM fields by providing resources that increasing post-Wesleyan mentorship and exposure to research excellence, all of which were fulfilled through this conference,” said Antonio Farias, vice president for equity and inclusion/Title IX officer. “It cannot go without saying that without Professor Taylor’s and Professor Etson’s holistic mentorship approach, these type of opportunities for our young scholars would not be possible.”

Kottos Awarded Engineering Grant from the National Science Foundation

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Professor Tsampikos Kottos

Tsampikos Kottos, professor of physics, professor of integrative sciences, professor of mathematics, was awarded a $400,000 Emerging Frontiers in Research and Innovation (EFRI) engineering grant from the National Science Foundation in October. This $2 million grant is equally split among a consortium of universities, including Stanford University, University of Minnesota, and University-Wisconsin-Madison, and will last for a period of four years.

The grant is associated with “New Light and Acoustic Wave Propagation: Breaking Reciprocity and Time-Reversal Symmetry” (NewLaw) and supports “engineering-led interdisciplinary research that challenges the notions of reciprocity, time-reversal symmetry and sensitivity to defects in wave propagation and field transport,” Kottos explained. 

Office of Naval Research Supports Microwave Limiter Study in Physics Department

Tsampikos Kottos, professor of physics, professor of mathematics, and his graduate student, Eleana Makri, are studying photonic limiters, which can be used to protect optical sensors (for example, the human eye) against laser-induced damage. Kottos recently received a grant to advance his research on microwave limiters, an important class of such protection devices.

Tsampikos Kottos, professor of physics, professor of mathematics, and his graduate student, Eleana Makri, design reflective power limiters, which reflect radiation back into space. Kottos recently received a grant to advance his research on microwave limiters, an important class of such protection devices.

With support from the Office of Naval Research, researchers in Wesleyan’s Physics Department are working on ways to protect optical sensors (for example, the human eye) against laser-induced damage.

In August, Tsampikos Kottos, professor of physics, professor of mathematics, received a three-year grant from the Office of Naval Research to further his designs of “Reflective Microwave Limiters.” Typical microwave limiters have the ability to block excessive radiation through absorption. However, absorption can lead to overheating, eventually causing the destruction of the limiter.

Kottos studies reflective power limiters with his graduate student Eleana Makri and Postdoctoral Research Associate Roney Thomas. The team hopes to develop realistic designs of microwave limiters that can tolerate high power radiation via direct reflection back in space (instead of absorbing it.)

“The limiter designs that we propose would reflect excess radiation back to space while providing broadband, omnidirectional protection from high-power electromagnetic radiation. As a result, they will be able to protect sensitive equipment by two or even three orders of magnitude higher power radiation than existing limiters,” Kottos explained.

The Office of Naval Research (ONR) is an organization within the U.S. Department of the Navy that coordinates, executes, and promotes the science and technology programs of the U.S. Navy and Marine Corps through schools, universities, government laboratories, nonprofit organizations, and for-profit organizations. Due to the rapid development of high power directed energy weapons technology, the ONR is supporting research that explores new materials and protection schemes of electromagnetically sensitive components from high power incident radiation.

Morgan Speaks on Laser-Induced Breakdowns at Plasma Physics Conference

Tom Morgan

Tom Morgan

Tom Morgan, Foss Professor of Physics, recently attended the 43rd Institute of Physics U.K. Plasma Physics Conference in Isle of Skye, Scotland. He presented a flash verbal presentation and a poster contribution dealing with the properties of water following focused laser induced breakdown.

After a plasma (a gas of ions and free electrons) is formed in water by laser breakdown, the energy is dissipated through light emission, shockwaves and cavitation bubbles. When the breakdown is close to the surface of the water, surface waves and water ejection from the surface up to heights of 60 cm also occur.

All of these phenomena have been observed in the laboratory at Wesleyan in conjunction with Lutz Huwel, professor of physics, Matt Mei ’18, and international collaborators. Joining the effort from abroad are Professor Tomoyuki Murakami, Seikei University, Tokyo, and Professor Bill Graham, Queen’s University, N. Ireland.

New effects not seen before have been observed, particularly near the surface at the air-water interface. The air-water interface is ubiquitous with applications to biology, environmental studies, chemical analysis and medicine, but its detailed behavior under different conditions is not well understood. The research uses both state of the art computer simulation and experimentation to elucidate the evolutionary dynamics and structure of bulk water and the air-water interface.

“Since the meeting was in Scotland, the researchers though it appropriate to try a liquid other than water and results were reported on whiskey as well,” Morgan said.

Makri Delivers Graduate Student Talk on Reflective Photonic Limiters

Eleana Makri, a PhD candidate in physics, spoke on “Reflective Photonic Limiters: a Novel Scheme for Sensor Protection” during the Graduate Student Speaker Series Feb. 10 in Exley Science Center. Photonic limiters are devices designed to transmit low-level radiation, while blocking electromagnetic pulses of power or total energy exceeding a certain threshold.

Eleana Makri, a PhD candidate in physics, spoke on “Reflective Photonic Limiters: a Novel Scheme for Sensor Protection” during the Graduate Student Speaker Series Feb. 10 in Exley Science Center. Photonic limiters are devices designed to transmit low-level radiation, while blocking electromagnetic pulses of power or total energy exceeding a certain threshold.

Starr’s Nanoparticle Research Published in Science

Professor Francis Starr and his collaborators are working to self-assemble a diamond-structured lattice at will from nanoscale particles.(Image by graduate student Hamed Emamy). 

Professor Francis Starr and his collaborators are working to self-assemble a diamond-structured lattice at will from nanoscale particles. (Image by graduate student Hamed Emamy).

Professor Francis Starr, graduate student Hamad Emamy and collaborators from the Brookhaven National Lab have co-authored a paper titled “Diamond Family of Nanoparticle Superlattices” published in the prestigious journal Science on Feb. 5. Starr is professor of physics and director of the College of Integrative Sciences.

Their work proposed a solution to a decades-long challenge to self-assemble a diamond-structured lattice at will from nanoscale particles.

“Such a diamond-lattice structure has long been sought after due to its potential applications as a light controlling device, including optical transistors, color-changing materials, and optical — as opposed to electronic — computing,” Starr said.

To solve this challenge, the team utilized the specific binding properties of DNA as a tool for materials science. Specifically, they created nanoscale “atoms” that consist of 15 nanometer gold nanoparticles coated with many single-stranded DNA. The single-stranded DNA act like binding arms to connect nanoparticle/DNA “atoms” by forming double-stranded DNA links, and analogue of traditional chemical bonds between atoms. By appropriate selection of the sequence and orientation of these DNA links, the nanoparticles will spontaneously arrange themselves into the desired structure.

“This self-assembly approach not only allows for highly specific order, but also offers the potential for tremendous savings in the cost of materials production, as compared to traditional methods used in the semi-conductor industry,” Starr explained.

Emamy, a graduate student in Starr’s lab, carried out numerical simulations that helped to develop the approach and explain how to stabilize the structure. Collaborators at Brookhaven experimentally synthesized and verified the structure and properties. The effort, Starr said, represented an ideal collaboration between experiments, theory and computation.

Wesleyan Hosts Conference for Undergraduate Women in Physics

More than 200 women undergraduates from the North East who are majoring in physics attended the American Physical Society Conferences for Undergraduate Women in Physics (CUWiP)

Attendees from the American Physical Society Conferences for Undergraduate Women in Physics gathered for a group photo. Wesleyan is the first liberal arts college to host a CUWiP.  Pictured in red at far left, assistant professor Chris Othon, and pictured at far right, assistant professor Meredith Hughes co-organized the conference at Wesleyan.

More than 200 women undergraduates from the Northeast attended the American Physical Society Conferences for Undergraduate Women in Physics (CUWiP) Jan. 15-17 at Wesleyan. Wesleyan was one of nine institutions from around the country to host a conference. (View an extensive recap of the conference starting on Page 8 of this APS newsletter.)

The APS CUWiP provides female physics majors with the opportunity to experience a professional conference, information about graduate school and professions in physics, and access to other women in physics with whom they can share experiences, advice and ideas.

The program included panel discussions about graduate school and careers in physics, presentations and discussions about women in physics, laboratory tours, student research talks, a student poster session, banquet and career fair.

Scientific American Editor Moskowitz ’05 is Woman Physicist of the Month

Clara Moskowitz. (Photo by John Van Vlack)

Clara Moskowitz ’05. (Photo by John Van Vlack)

The American Physical Society (APS) named Clara Moskowitz ’05 the Woman Physicist of the Month for December 2015. A senior editor at Scientific American, she was an astronomy and physics double major at Wesleyan. It was in her senior year that she discovered her “favorite part” of her undergraduate career: her thesis.

“I was fascinated by science from a very young age,” she says, “but so many people feel separated from science—as though they can’t get it. I realized that I like writing and I like to communicate the concepts for nonscientists.” After earning a graduate degree in science journalism at the University of California, Santa Cruz, Moskowitz then joined the online publication Space.com, where she covered NASA’s space shuttle missions and other astronomy news. Two years ago, she joined the venerable Scientific American: “We try to keep it current and stay true to its legacy,” she notes.

Moskowitz recalls her favorite assignment at the magazine—which she focused on both historic import and present application: she served as editor of the theme issue on 100 years of general relativity (Sept. 2015, Vol. 313, Issue 3).
“Einstein is such a fascinating figure; he singlehandedly revolutionized science just by thinking about problems: he went through in his mind exactly what it would be like to ride a beam of light. A hundred years after he proposed the theory, we are still thinking about it, still using it—in our cellphones, GPS devices, and satellites.

“His realization that gravity is not so much a force that pulls things together—but rather that it comes from the shape of space and time—is such a beautiful idea.”

As for her success with the project, editor-in-chief Mariette DiChristina wrote, “Issue editor Clara Moskowitz and the team have created a special report that is profound yet playful and sparkles with the wonder of discovery—rather like the great man himself. We hope you enjoy reading [this issue] as much as we did putting it together.”

Said Moskowitz, “I’m constantly working hard to make science understandable. I want everyone to see what’s so cool about it.”

Reached at the American Astronomical Society’s January 2016 meeting, which she was covering for Scientific American, Moskowitz was most excited about a recent talk she attended about astronomers planning to use telescopes all over the world in conjunction, in order to capture the event horizon of the black hole that astronomers think lies at the center of our galaxy. The project—which could further prove the theory of general relativity, or call for modifications—will take its first images of the black hole in 2017.

“A lot of us are on the edge of our seats until we get the results,” Moskowitz said.

Moskowitz also was back at Wesleyan on Jan. 16 for the Conference for Undergraduate Women in Physics, where she spoke about her career path. She will present a Physics Department colloquium on March 3 about science journalism.

Morgan Speaks at Atomic Molecular Optical Workshop in Mexico

Tom Morgan

Tom Morgan

Tom Morgan, the Foss Professor of Physics, recently attended an Atomic Molecular Optical International Workshop held in Cuernavaca, Mexico.

Morgan presented two invited talks, one on highly excited unusual electronic configurations of molecular hydrogen produced by laser excitation and another on laser interactions at the interface between water and air. These topics elicit novel dynamics and provide a different perspective on H2 and H2O behavior.

He also took the opportunity to reconnect with a Mexican colleague, Professor Carmen Cisneros, Institute of Physics, University of Mexico, organizer of the workshop, with whom Morgan has collaborated in the past.