Physics Newsblog

Author: Steve Mintz

Umbargers Establish Fund to Advance Undergraduate Research in Physics

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John and Kathy Umbarger
John and Kathy Umbarger share a happy moment

C. John ’64 and Kathryn O. Umbarger created the C. John and Kathryn Umbarger Physics Fund at Michigan Technological University. The annual fund provides financial support to Michigan Tech’s Department of Physics for undergraduate and graduate student projects and research. 

A Giving Tradition Since 1988

Giving directly to the Michigan Tech physics program is nothing new for the Umbargers. They have been doing so since 1988. In fact, supporting education and learning is something near and dear to the Umbargers. John believes, “It doesn’t matter where you start but what you do in life. With learning and an education, you can do just about anything.” 

John Umbarger
John Umbarger in the 1964 Keweenawan

“Thanks to my Michigan Tech education, I was fortunate enough to meet the love of my life, embark on a terrific career, and start and nurture a terrific family,” John said. “Both Kathy and I have been blessed. We have a sound financial footing, and we want to help Michigan Tech students embark on a similar journey. We hope and encourage other Tech graduates to consider doing the same.”

Physics Advocates Create Opportunities

“Kathy and John have been strong advocates of the physics program at Michigan Tech and provided generous support for the undergraduate research fellowships over the past years,” said Dr. Ravindra Pandey, Department Chair and Professor of Physics. “We are excited for the tremendous opportunities our students get to apply their learning in the lab, practice skills and acquire knowledge that will help them on their future journey and career.”

Kathy Olson Umbarger
Kathy Olson (now Umbarger) was crowned queen of the 1964 Military Ball

The fund enables projects like Breanna Patz’s “Ultralight Sunflower Starshade Structural Design – NASA challenge” under the guidance of faculty advisor Dr. Jacek Borysow. Breanna is working to develop a sunshade that helps those using ground-based telescopes to get an unobstructed view of exoplanets by blocking out the light of stars. As a result, observers can better see the light reflected by a planet and understand the features (e.g., oceans, land masses, atmosphere) of that planet. NASA’s challenge is to create a deployable sunshade for use in space.

Benj Sloma’s work under the guidance of faculty advisor Claudio Mazzoleni is another example. ”Use of Dynamic Photoacoustic Spectroscopy to Measure Light Absorbance of Aerosols” helps researchers to study particles containing black carbon (BC) produced during incomplete combustion and their interactions with clouds. “We could not offer opportunities like these to students without the generosity of donors like the Umbargers,” said Pandey.

Umbargers Pay It Forward

Paying it forward is a common theme for the Umbargers. “We had teachers and educators that made positive impacts on our lives. It’s important for us to pay it forward and give the next generation the same opportunities we had. Plus it is energizing to talk and work with young people,” he said.

How else has John been paying it forward? He teaches classes each week to 12-13 students in the Benton and Franklin Counties Juvenile Justice Center; a role he started in the late ’90s. He founded the Tri-Cities Crystal Apple Awards program, recognizing local teachers. And John just retired from the Pasco School District Vocational Program Board, which he initiated in 1997. This self-funding program enables students to build homes (23 were built in 25 years) to be sold on the open market, teaching valuable skills to hundreds of students. These and countless other examples of community work earned him recognition as Tri-Citian of the Year in 2010.

Michigan Tech Glee Club singing in 1964
John Umbarger (back row, second from left) sings with the Glee Club

John has a bachelor’s degree in physics, a master’s in management, a doctorate in nuclear physics, and served two post-doctoral fellowships. He holds five U.S. patents and was employed at Los Alamos National Laboratory until 1997, spending 26 years with the Department of Energy lab. John and Kathy moved to Washington state in 1997, where John took a job with Fluor Hanford in economic development and community programs. He retired in 2008.

Would You Like To Give?

If you would like to inquire about giving opportunities in the Physics Department or elsewhere at Tech, please contact Karin Van Dyke, Michigan Tech University, Director of Advancement, 1400 Townsend Drive, Houghton, MI 49931. Email: kvandyke@mtu.edu. Phone: 906-487-2464.

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Physicists develop a linear response theory for open systems having exceptional points

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Linear analysis plays a central role in science and engineering. Even when dealing with nonlinear systems, understanding the linear response is often crucial for gaining insight into the underlying complex dynamics. In recent years, there has been a great interest in studying open systems that exchange energy with a surrounding reservoir. In particular, it has been demonstrated that open systems whose spectra exhibit non-Hermitian singularities called exceptional points can demonstrate a host of intriguing effects with potential applications in building new lasers and sensors.


At an exceptional point, two or modes become exactly identical. To better understand this, let us consider how drums produce sound. The membrane of the drum is fixed along its perimeter but free to vibrate in the middle. As a result, the membrane can move in different ways, each of which is called a mode and exhibits a different sound frequency. When two different modes oscillate at the same frequency, they are called degenerate. Exceptional points are very peculiar degeneracies in the sense that not only the frequencies of the modes are identical but also the oscillations themselves. These points can exist only in open, non-Hermitian systems with no analog in closed, Hermitian systems.


Over the past years, ad-hoc analysis of the scattering coefficients of non-Hermitian systems having exceptional points has revealed a puzzling result, namely that sometimes their frequency response (the relation between an output and input signals after interacting with the system as a function of the input signal’s frequency) can be Lorentzian or super Lorentzian (i.e. a Lorentzian raised to an integer power). In contrast, the response of a standard linear, isolated oscillator (excluding situations where Fano lineshapes can arise) is always Lorentzian.


Now, an international team of physicists led by Prof. Ramy El-Ganainy from Michigan Technological University, along with several collaborators from Penn State, the Humboldt University in Berlin, and the University of Central Florida, has tackled this problem in their recent Nature Communications article titled “Linear response theory of open systems with exceptional points”. In that work, the team presents a systematic analysis of the linear response of non-Hermitian systems having exceptional points. Importantly, they derive a closed-form expression for the resolvent operator quantifying the system’s response in terms of the right and left eigenvectors and Jordan canonical vectors associated with the underlying Hamiltonian.

A schematic representation of a complex non-Hermitian open system with many degrees of freedom made of coupled optical microdisk cavities. The linear response theory developed in this work provides a full characterization of the relation between output and input signals (indicated by green and yellow arrows, respectively) in terms of the eigenmodes and the canonical states of the underlying non-Hermitian Hamiltonian.


“In contrast to previous expansions of the resolvent operator in terms of the Hamiltonian itself, the formalism developed here provides direct access to the linear response of the system and demonstrates exactly when and how Lorentzian and super-Lorentzian responses arise” says Prof. El-Ganainy. “As it turned out, the nature of the response is determined by the excitation (input) and collection (output) channels” says Amin Hashemi, the first author of the manuscript. The presented theory describes this behavior in detail and is generic enough to apply to any non-Hermitian systems having any number of exceptional points of any order, which makes it instrumental for studying non-Hermitian systems with large degrees of freedom.


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Lucas Simonson, physics PhD candidate awarded scholarship to study in Germany

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Lucas Simonson is off to study in Germany

Lucas Simonson has been awarded a scholarship by the German Academic Exchange Service (DAAD). He will study at the Max Planck Institute for the Physics of Complex Systems in Dresden.

The German DAAD is a joint organization of the universities and other institutions of higher education in the Federal Republic of Germany, and the world’s largest funding organization of its kind. Supported by public funds, the DAAD promotes international academic cooperation, especially through the exchange of students and academics. DAAD scholarships are awarded by selection committees comprising a panel of independent academics.

He looks forward to studying under Professor Kurt Busch starting October 2022 to the end of April 2023. “The rationale for this trip is that joining my advisor in Germany will allow me to proceed with my research activities at a fast pace without any delay due to his absence. It will also allow me to interact with world-class optics research groups at the Humboldt-Universität Berlin,” he says. “It’s a significant milestone in my academic career and will allow me to experience other cultures outside of those in the US to broaden my worldview,” says Lucas.

Studying in Germany adds another frame of reference in his study of physics. “Lucas is bringing a unique perspective to our group by combining an interdisciplinary education in both electrical engineering and physics,” says Ramy El-Ganainy, associate professor of physics.

Lucas obtained an MS in Applied Physics (back in the spring of 2021). He entered the PhD candidacy at the end of this past spring semester. Upon getting his PhD, Lucas plans to pursue R&D-related work at Ft. Belvoir in Virginia for The Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance and Reconnaissance (C5ISR) Center, the U.S. Army’s information technologies and integrated systems center.

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Physics Major Anthony Palmer Wins Best Poster at Computing [MTU] Showcase

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Michigan Tech physics and applied and computational mathematics double major Anthony Palmer, along with computer science PhD candidate Elijah Cobb, won the best poster recently in the Computing [MTU] Showcase for “Universal Sensor Description Schema: An extensible metalanguage to support heterogenous, evolving sensor data.”

Image of Anthony Palmer and Elijah Cobb in front of their poster at Michigan Tech’s Computing [MTU] Showcase
Anthony Palmer (left) and Elijah Cobb present their poster at Michigan Tech’s Computing [MTU] Showcase

Collecting and processing underwater sensor data is a critical need for U.S. Navy operations. Differences in sensor data types and forms presents a challenge for complete and accurate use of these data. The Universal Sensor Description Schema (USDS) project seeks to design, evaluate, and deploy a unified, extensible metalanguage for supporting legacy and future sensor data across multiple programming languages and environments. Michigan Tech is collaborating with Applied Research in Acoustics LLC to develop a robust programming environment for development of data-intensive applications.

Anthony came up with the idea for the project while interning at ARiA (a small research-and-development firm serving the Navy, government and industry). It’s been the basis for his senior thesis in physics. Anthony says “This project in particular has helped me learn alot about how programming languages work and are made. It also helped me learn a new functional programming language called “Racket”. Finally, it introduced me to some awesome people in the MTU computer science department including my partner Elijah Cobb and my advisor, Dr. Charles Wallace.”

Eye-opening describes the experience for Anthony.  He says, “I would say that I was surprised by the intricacy of how programming languages are built and function. I would also say that it was unexpected how useful recursion can be for solving problems in computing.” Recursion reduces time complexity, adds clarity and reduces the time needed to write and debug code.

Anthony graduates in a few short weeks. HIs attention will turn to the Navy, where he will be a submarine officer. Eventually he hopes to go into graduate school.

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