Research team
Mark Siemens
Dr. Mark Siemens is a professor in the Department of Physics and Astronomy at the University of Denver. He has been at DU since 2010, and is interested in exploring the careful manipulation of light and its use to measure and control the flow of energy in solid state materials.
We are always excited to hear from folks who have questions about our research or are interested in collaborating!
Graduate researchers
Ethan Cole
Ethan Cole graduated from UNC Asheville in 2020 with a B.S. in Physics and minored in math and astronomy. As an undergraduate, his research focused on onboarding a new spectrometer for Raman spectroscopy with Dr. James Perkins. As a graduate student, Ethan will research spectroscopy of thin film semiconductors with Dr. Mark Siemens. In his free time, Ethan likes hiking, reading, playing golf, and chess
Patrick Ford
Patrick Ford received a B.S in Physics and Applied Mathematics at Metropolitan State University of Denver in 2019. As an undergraduate, Patrick built numerical models for SQUID research and was involved in production for the SuperCDMS dark matter detector project in the CU Denver Superconducting Electronics laboratory studying under Professor Martin Huber. As a graduate student, Patrick hopes to discover new insights into the nature of and manipulation of light with orbital angular momentum in the non-linear regime. Other than physics, Patrick's life is consumed by music and a desire to be outside.
Somayeh Ghazanfarpour
Somayeh Ghazanfarpour is a graduate student at DU from Iran. In 2015, she obtained her B.S. in Atomic and Molecular physic at Vali-e-Asr University of Rafsanjan where she did research in Inverted Polymeric Solar cells in Laboratory of Solar Cells, Thin Films and Nanostructures. In 2017, Somayeh also received her M.SC in Atomic and Molecular Physics at Arak University where she researched on physical and optical properties of modified electrodialysis membranes by nanoparticles. In her research, she hopes to get new insight to thin-film semiconductors with 2D spectroscopy in future years. In her free time, Somayeh spends her time by cooking, reading historical books and biographies, watching movies, and swimming.
Adam Halaoui
Adam Halaoui graduated from the University of Toledo in 2019 and has undergraduate degrees in physics, math and high school education. While an undergraduate student Adam worked under Professor Randy Ellingson building and writing software for measurement systems and characterizing photovoltaic materials using transient absorption and other spectroscopic methods. Adam is a student at The University of Denver working under Professor Mark Siemens using multidimensional coherent spectroscopy to study thin-film semi-conductors. In his vast spare time, Adam likes music, reading books, climbing and cooking.
Oliver Schwarm
Oliver earned his physics BA in 2020 from Whitman College in Walla Walla Washington. As an undergraduate his research experience included computationally identifying noise sources for the Laser Interferometer Gravitational-Wave Observatory (LIGO), and an REU on investigating aging mechanisms in ferroelectric materials. Now in the Siemens Lab at DU, Oliver works on using multidimensional coherent spectroscopy to characterize photovoltaic candidates and other novel semiconductors. After a day in the lab, Oliver likes to unwind with Dungeons & Dragons and other forms of creative gaming.
Drew Voitiv
Andrew (Drew) Voitiv came from Springfield, Missouri, to the University of Denver where he earned a BSc in Physics in 2019. Since his time as an undergraduate, Drew has researched in the Siemens Lab working on experiments generating, controlling, and measuring optical vortices. Drew has a passion for STEM outreach and is an active member of the Society of Physics Students at DU. Outside of physics, Drew sings in the DU Men’s Choir and dances swing and tango on campus and in the greater Denver-Boulder community.
Samantha Weckerly
Samantha Weckerly is from Nashville, TN. She graduated from the University of Alabama in Huntsville with a B.S. in Physics. During her undergraduate studies, she researched various thin films, using an Ellipsometer to measure properties such as thickness and refractive index. She has also participated in research involving polarization within a turbulence lab and vortex retarders, and assisted in troubleshooting and fine tuning pockels cells and interferometers. She looks forward to increasing her knowledge of optics at DU. Outside of Physics, she enjoys competitive gymnastics and stargazing/astrophotography.
Undergraduate researchers
Jafar Al Habib
Research: Holography and pure generation of optical vortices
Lark Bradsby
Research: Holography and phase-resolved measurement of optical vortices
Will Gross
Research: Spectroscopy of perovskite photovoltaic devices
William Morris
Research: Optical vortex generation and propgation
Rylie Mundell
Research: Optical vortex interference
Jacqueline Roth
Research: Generation and control of optical vortices
Jon Weber
Research: Vector vortex beams
External collaborators
Optical vortex motion
Generation, measurements, and applications of light’s orbital angular momentum
Spectroscopic measurement of carrier transport in poervskite photovoltaics
Theory of light-matter interactions with orbital angular momentum
Group alumni
Gina Eldridge
2012 BS in Physics and Mathematics. In her senior thesis, Gina studied four wave mixing in polymer materials for solar conversion applications. Gina got an MS in Physics at th Colorado School of Mines and is currently an optical engineer at Apple.
Pampa Devi
Pampa joined us as a graduate student intern in the fall of 2012, and she helped build our multidimensional spectroscopy setup.
Nurin Ludin
2014 BS in Physics. In her time in our lab, Nurin investigated thermal bystander effects in cells.
Garrett Williams
2014 BS in Physics and Mathematics. In Garrett’s senior thesis, he demonstrated the generation laser beams with orbital angular momentum (OAM) using parts from a projector - an important first step in our experiments with light’s OAM.
Samantha Molnar
2015 BS in Physics. Sam set up the magneto-optic Kerr effect experiment in our lab. She is currently a Computer Science graduate student at the University of Colorado Boulder.
Rebecca Conrad
2015 BS in Mathematics. In our lab Rebecca calculated analytical lineshapes for multidimensional spectroscopy, and her research was published in Optics Letters. She is currently an engineer at Lockheed Martin.
Joshua Bell
2015 MS in Physics. Aside from keeping our lasers happy, Josh also set up our 2D coherent spectroscopy experiment. His research was published in Optics Letters. He is currently an applications engineer with Nikon.
Cameron (Cam) Hickert
2016 BS in Physics. Cam optimized the magneto-optic Kerr effect experimental apparatus and the effect of multilayering on the magnetization of metalic film films.
Chris Racz
2016 BS in Physics. Chris built a heat pipe oven for atomic vapor spectroscopy and measured propagation effects of focused laser beams. He currently owns a physics tutoring business with his wife.
Jack Maurer
2016 BS in Physics and Chemistry. Jack built a transient absorption experiment with a pulsed laser to measureexciton dynamics in colloidal PbS quantum dots. He is currently a PhD student at the Unviersity of Oregon.
Melia Morris
2016 high school graduate, and undergraduate researcher in summer 2016 and 2017. Melia designed a system to use a diffraction grating to measure light’s orbital angular momentum.
Maren Blair
2017 BS in Physics. Maren designed and built our first experiments studying heat transport in tissue for cancer treatment. She is currently a physics teacher.
Brad Becker
2017 BS in Physics. Brad worked on our magneto-optics experiment.
Sam Alperin
2017 BS in Physics. Sam built a novel quantitative OAM measurement setup, explored the angular momentum properties of fractional OAM beams, and discovered that light behaves as a quantum fluid. His work was published in Optics Letters and Physical Review Letters (twice!). He is currently a PhD student in Applied Math at Cambridge.
Julia Farrell
2018 BS in Computer Science. Julia built our first setup to measure the temperature dependence of orbital angular momentum of light generated in an optical fiber.
Mark Phelps
2018 BS in Physics. Mark calculated electron-phonon coupling in quantum dots and built an experimental setup to couple light’s orbital angular momentum to electrons.
Daniel Hammerland
2018 MS in Physics. Dan built our first Raman spectroscopy setup, learned to do TMD exfoliation, and designed and built and ultrafast Raman system as well. He is currently a PhD student at ETH Zurich.
Andrew Johnson
2018 MA in Physics. Andrew built experiments to look for copuling between light’s orbital angular momentum and electrons in quantum rings and dots.
Alaa Bahamran
2019 PhD in Physics. Alaa studied light-matter interactions with orbital angular momentum in quantum dots. She is now an assistant professor at King Abdulaziz University in Audi Arabia.
Brian Green
2019 PhD in Physics. Brian used transient thermoreflectance to measure thermal transport dynamics in nanostructures. He is now a postdoctoral researcher at the National Renewable Energy Laboratory (NREL) in Golden, Colorado.
Abi Grotelueschen
2019 BS in Physics. Abi built an experiment for phase-resolved imaging of propagating laser speckle, and her work was published in Physical Review Letters. She is currently a Physicist at Peraton.
Geoffrey Diederich
2019 PhD in Physics. Geoff built and comissioned our original 2D spectroscopy experiment, and did our first measurements on perovskite films. He is currently a postdoc at the University of Washington.
Maria Rios-Gomez
2020 BA in Biological Sciences and French. Maria built microscopes for studying few-layer materials, including our Raman setup.
Austen Applebee
2020 BS in Physics. Austen experimentally studied optical vortex propagation in optical fiber.
Ryan Davis
2020 BS in Physics. Ryan built an experimental setup to simultaneously measure photoluniscence and photocurrent from a sola cell.
Will Holtzmann
2020 BS in Physics. Will measured vortex splitting and formation in laser beams. He is currently a physics graduate student at the Univerity of Washington.
Rebecca McCubbin
2020 BS in Physics. Becca built an experimental setup to simultaneously measure photoluniscence and photocurrent from a sola cell.
Emilee Wurtz
2020 BS in Physics. Emilee worked on generating and measuring optical orbital angular momentum. She is currently a physics graduate student at Boston University.
Charles Payne
2020 MA in Physics. Charles studied optical vortex formation and propagation. He is currently a staff scientist at Los Alamos National Lab.
Jasmine Andersen
2021 PhD in Physics, based on her work on optical hydrodynamics of vortices.
Dawson Hewatt
2022 BS in Physics. Dawson made his own perovskite photovoltaics and studied them with multiple forms of spectrosocpy. He is currently a physics graduate student at the University of Colorado.
Leah Huzjak
2022 BS in Physics and Mathematics. Leah experimentally measured vortex nucleation behind a blockage.
Miguel Turcios-Flores
2022 BS in Electrical Engineering. Miguel worked to interface and automate our high-vacuum and low-temperature systems for spectroscopy.
Zhe Kan
2022 postdoctoral scholar. Zhe Kan was instrumental in setting up our first photon entanglement measurements.
Patrick Fowler
2023 graduate student. Patrick demonstrated a new method for superresolution imaging.
Zecheng You
2023 BS in Physics and Mathematics. Zecheng built our setup for generating vector vortices. He is currently a physics graduate student at the University of Michigan.
Lillian Sartor
2023 BS in Physics. Lillian built a custom setup to test the idea that a fingerprint genreates a unique vortex pattern.
Kate Pletcher
2023 BS in Physics and Mathematics. Kate built a custom optical setup to measure tilted optical vortices in both imaging and Fourier (far-field) domains. She is currently a physics graduate student at Michigan State Unviersity.
Group awards
2023
Drew Voitiv received the Outstanding Graduate Researcher award from the college of Natural Sciences and Mathematics.
Lark Bradsby and Jon Weber were awarded research grants from DU’s Undergraduate Research Center
2022
Drew Voitiv received a graduate scholarship from Phi Beta Kappa, Alpha Association of Colorado.
Kate Pletcher and Will Gross were awarded research grants from DU’s Undergraduate Research Center
Leah Huzjak received the Summitt Award, recognizing a student career of leadership, scholarship, and ambassadorship for DU.
Dawson Hewatt received the Outstanding Student Award, recognizing the DU undergraduate who has had the most spectacular year in academics, leadership, scholarship, and community engagement.
Leah Huzjak received the Outstanding Service Award from SPS National, “For her critical leadership of the Society of Physics Students at the University of Denver through her warm and inclusive community-building in the midst of COVID restrictions, her active pursuit of outreach opportunities and engagement with community partners, and her persistent use of cat and physics memes"
Kate Pletcher received the AWIS Kirsten R. Lorentzen Award, given to one student who excels in her studies and is exceptionally well-rounded.
2021
Kate Pletcher and Kylie Mundell were awarded research grants from DU’s Undergraduate Research Center
Jasmine Andersen was awarded a Graduate Studies for Dissertation Fellowship award from DU’s office of graduate studies
Mark Siemens received the “Excellence in Teaching” award from NSM college
2020
Lily Sartor and Dawson Hewatt were awarded research grants from DU’s Undergraduate Research Center
Mark Siemens was promoted to full professor in the Department of Physics & Astronomy at the University of Denver..
Geoff Diederich was awarded a Graduate Studies for Dissertation Fellowship award from DU’s office of graduate studies
Drew Voitiv received DU’s Crimson & Gold award, DU’s highest honor, given for exemplary academic performance, leadership, community service, campus involvement, character, and pride in the University
2019
Austen Applebee, Martin Luepker, Leah Huzjak, Kate Pletcher, and Becca McCubbin were awarded research grants from DU’s Undergraduate Research Center
Jasmine Andersen was selected to present her research at a keynote talk at the DU Research Day, the only one from DU’s college of Natural Sciences and Mathematics. Jasmine was also elected President of the Colorado/Wyoming section of the American Association of Physics Teachers.
Geoff Diederich was awarded a Graduate Studies for Dissertation Fellowship award from DU’s office of graduate studies
Drew Voitiv received DU’s Crimson & Gold award, DU’s highest honor, one of only five graduating seniors recognized for exemplary academic performance, leadership, community service, campus involvement, character, and pride in the University
Mark was a finalist for the SPS National Outstanding Chapter Advisor award.
Mark received the “Excellence in Research” award from DU’s college of Natural Sciences and Mathematics..
2018
Diego Daza-Diaz, Emilee Wurtz, Mackenzie Looney, and Abi Grotelueschen were awarded research grants from DU’s Undergraduate Research Center
Will Holtzmann and Abi Grotelueschen were awarded research abroad EuroScholars
2017
Drew Voitiv, Will Holtzmann, and Alex Werner received research grants from DU’s Undergraduate Research Center
Jasmine Knudsen and Dan Hammerland were awarded DU’s “Doctoral Fellowship for Inclusive Engagement”
Mark has been elected chair of the “Ultrafast Optical Phenomena” technical group of the Optical Society of America
2016
Sam Alperin, Mark Phelps, Drew Voitiv, and Julia Farrell received research grants from DU’s Undergraduate Research Center
Mark received a 2016 Fulbright Fellowship to support a research visit to Argentina
Mark was awarded a Franklin Research Grant from the American Philosophical Society
Mark received an NSF CAREER award
2015
Brad Becker, Jack Maurer, Maren Blair, Julia Farrell, and Akele Knecht received research grants from DU’s Undergraduate Research Center
DU’s Society of Physics Students (Mark is the faculty advisor) won the Blake Lilly Award for exceptional engagement in public science outreach
Mark was recognized as “Outstanding Junior Faculty” from DU’s Division of Natural Sciences & Mathematics
2014
Connor Thiret, Samantha Molnar, Sam Alperin, and Chris Racz received research grants from DU’s Undergraduate Research Center
Mark received the “Outstanding Faculty Service” award from DU’s Division of Natural Sciences & Mathematics
2013
Rebecca Conrad, Garrett Williams, Jake Gold, Chris Racz, and Samanntha Rehman received research grants from DU’s Undergraduate Research Center
2012
Garrett Williams and Jake Gold received research grants from DU’s Undergraduate Research Center
Mark received a “Doctoral New Investigator” award from the American Chemical Society, Petroleum Research Fund
2011
Gina Eldridge received a research grant from DU’s Undergraduate Research Center
2010
Gina Eldridge received a research grant from DU’s Undergraduate Research Center
