Advanced Atomic Design Lab
The Alex Demkov Group

The Demkov Group Members
Demkov Group, December 2017
Left to right, front to back: Wei Guo, Ali Hamze, Fatima Al Quaiti, Lingyuan Gao, Tobias Hadamek,
Alex Demkov, Wente Li, Agham Posadas, Elliot Ortmann, Marc Reynaud, Marc Reynaud, Donghan Shin
Absent: Jackie Geler-Kremer

Principal Investigator

Alex Demkov
Principal Investigator, Prof. Alex Demkov
Office: RLM 13.206
Phone: (512) 471-8560
Fax: (512) 471-9637 About:
Alex Demkov is a professor of Physics at The University of Texas at Austin. He received his Ph.D. in theoretical physics in 1995 from Arizona State University (ASU). In 1995-1997, he was a postdoctoral researcher at ASU. In 1997-2005, he was a principal staff scientist in Motorola.s R&D organization providing theoretical support for the development of low- and high-k dielectric materials. In 2005, he joined the faculty of the Physics Department at the University of Texas at Austin. Prof. Demkov has published over 200 research papers and has been awarded nine U.S. patents. He has written, contributed to and edited several books. Demkov received the 2006 NSF CAREER award, 2011 IBM Faculty Award, and 2014 Excellence in Leadership Award of the American Vacuum Society. He is a Senior Member of IEEE and Fellow of the American Physical Society.

Current Members

Agham Posadas
Senior Research Scientist, Dr. Agham Posadas
Office: RLM 7.316
Phone: (512) 232-4242
E-mail
About:
Agham Posadas is managing the Oxide MBE lab at the University of Texas at Austin. He received his Ph.D. in Applied Physics from Yale University in 2007, and his M.S. in Materials Science and Engineering (in 1997) and B.S. in Applied Physics (in 1994) from the University of the Philippines. His prior scientific work includes bulk growth and characterization of high-Tc superconductors at the University of the Philippines, and fabrication of Si and SiGe heterostructures using molecular beam epitaxy (MBE) as a research student at the University of Tokyo. At Yale, his Ph.D. research involved the growth and characterization of functional oxide thin films on semiconductors using both rf sputtering and MBE. He also has expertise in magnetic and transport measurements as well as in thin film crystallographic characterization using four-circle x-ray diffractometry. He joined the University of Texas at Austin in 2009 becoming one of the principal researchers in the new Materials Physics Laboratory headed by Prof. Demkov. He has co-authored over 20 research papers on various oxide thin film heterostructures and a chapter in a new textbook on ferroelectric materials.

Tobias Hadamek
Graduate Student, Tobias Hadamek
Office: RLM 7.204
Email: hadamek [AT] physics [DOT] utexas [DOT] edu
About:
Toby's research is concentrating on epitaxial integration of rare earth sesquioxides on the III-V semiconductor gallium nitride (GaN) by MBE utilizing Zintl-interlayers. The broader motivation for his research is given by the consideration that as semiconductor technology moves beyond silicon, GaN is seen as a strong contender for high-power, high-temperature and high-frequency applications. Toby's research is conducted in the Materials Physics Laboratory at UT Austin and involves the growth of the materials in UHV and subsequent determination of materials properties by the use of x-ray and electron diffraction and photoelectron spectroscopy. Toby started his PhD in the Demkov group in the summer of 2015 after having obtained a MA in Physics from UT in 2014 and a BS in Physics from University of Würzburg, Germany in 2013.

Donghan Shin
Graduate Student, Donghan Shin
Office:RLM 7.208
Phone: (512) 232-7535
About:
Donghan Shin joined the Physics Department at the University of Texas at Austin as a graduate student in 2012 after receiving his B.S. and M.S. in physics from the Yonsei University in Seoul, Korea. He is currently working on research about point defects in titanium dioxide (TiO2) using first-principle calcualtions and tight-binding models. He is also interested in the simulation of X-ray Core LEvel Spectroscopy and ARPES.

Elliott Ortmann
Graduate Studten, Elliott Ortmann
Office:
Phone:
About:
Elliott joined the Physics Department at the University of Texas at Austin as a graduate student in the Fall of 2013. Before arriving at UT, he earned a Bachelor of Science in Physics and Mathematics from Tulane University in New Orleans, LA. At Tulane, Elliott worked in Professor Zhiqiang Mao's Low Temperature Condensed Matter Physics research group, studying the magnetic and electronic properties of single crystals of doped Sr2RuO4, an exotic, spin-triplet superconductor. Since joining the Demkov group in the Fall of 2014, Elliott has been working on growing oxide quantum well heterostructures using molecular beam epitaxy (MBE). Specifically, he is interested in studying the intersubband transitions in oxide quantum wells and developing the means to controllably tune the frequency of these transitions by utilizing the many degrees of freedom found in oxide heterostructures.

Ali Hamze
Graduate Student, Ali Hamze
Office: RLM 7.204
Phone:
About: Ali started working on his PhD in physics at UT Austin in the Fall semester of 2013. He worked in high-energy physics for a year and a half before deciding to switch to condensed matter. He joined the Demkov group in late 2014. Ali's current research is focused on using density functional theory to model the growth of aluminum on SrTiO3, non-linear optical responses in BaTiO3, and gradient ferroelectric systems.

Jackie Kremer
Graduate Student, Jackie Kremer
Office:
Phone:
About: Jackie started her graduate studies at UT Austin in the Fall of 2015 after finishing her B.S. in Physics from University of California, Santa Barbara. Jackie's undergraduate research was with Elisabeth Gwinn's group at UCSB where she researched the photostability of DNA templated silver nanoclusters. She joined the Demkov group in the Fall of 2015 and is working on growing Sr on SrTiO3 in using MBE and analyzing the interface using XPS.

Wei Guo
Graduate Student, Wei Guo
Office:
Phone:
About: In June 2014, Wei Guo received his B.S. in physics from Nanjing University in China. At September in the same year he joined the Physics Department of UT-Austin. He has used SVD to analyze 2D ultrafast laser spectra in his undergraduate. He decided to switch to film growth and join the group at summer 2015. Now he is working on the Pt growth on STO by MBE and using XPS etc to explore the properties of this interface.

Marc Reynaud
Graduate Student, Marc Reynaud
Office: RLM 7.202
Phone:
About: Marc started working on his PHD in physics in the fall of 2016 after he completed his B.S. in Physics and Materials Science & Engineering at Rutgers University. He joined Professor Demkov's group in summer 2017, and is currently working on growth of BTO on Si/Ge with MBE and characterization of the surface and the electro-optic properties of the material.

Fatima Al-Quaiti
Graduate Student, Fatima Al-Quaiti
Office:
Phone:
About: In May of 2017, Fatima Al-Quaiti graduated from St. Mary's University at San Antonio with a Bachelors of Science in Chemistry and a Bachelors of Arts in Mathematics. In Fall of 2017, she came to UT Austin to pursue a PhD in Physical Chemistry and joined the Demkov group.

Wente Li
Graduate Student, Wente Li
Office: RLM 7.202
Phone:
About: In August 2016, Wente earned his B.S. in physics from Zhejiang University, China. At the same year, he started his graduate studies at the Department of Physics, UT Austin. He joined Prof. Alex Demkov¿s group in September, 2017. His current research interest is developing a theory of point defects in transition oxides by using both analytical and first principle calculations.

Demkov Group Alumni

Lingyuan Gao
Graduate Student, Lingyuan Gao
Office: RLM 7.208
Phone: (512) 232-7535
About:
Lingyuan earned his B.S. from Peking University in China and joined the Demkov group in the Spring of 2014. His current research interests include investigating causes of anomalous elastic behavior in SrTiO3 as well as comparative studies of work function calculations for metallic clusters in real space DFT.

Patrick Ponath
Graduate Student, Patrick Ponath
Office: RLM 7.202
Phone: (512) 232-7573
E-mail
About:
In 2010 Patrick received his B.Sc. in physics from the Julius-Maximilians-University of Wuerzburg, graduated with a MA in physics from the University of Texas at Austin in 2011 and joined the group in 2012. Currently, he is doing research on the epitaxial growth of barium titanate (BaTiO3) on germanium substrates using molecular beam epitaxy. Additional spectroscopic and diffraction measurements are carried out to determine the quality and polarization of the ferroelectric BaTiO3 films. In conjunction with germanium, BaTiO3 is an excellent candidate for a ferroelectric field effect transistor with applications in nonvolatile logic and memory devices.

Patrick graduated with his PhD in July 2017 and has accepted a position at Lam Research.

Kristy Kormondy
Graduate Student, Kristy Kormondy
Office: RLM 7.204
Phone: (512) 232-7588
Website
About:
Kristy Kormondy joined the Physics Department at the University of Texas at Austin as a graduate student in 2011 after receiving her B.S. in physics from the University of Central Florida. Her current research focuses on epitaxial growth of perovskites on vicinal surfaces. Even nominally flat surfaces have steps, and these steps can influence the growth and quality of deposited films. Using reflection high-energy electron diffraction (RHEED) and other methods, Kristy investigates the ways in which the finite terraces resulting from intentional miscut of the Si (100) surface affect the growth kinetics and film characteristics of SrTiO3.

Kristy graduated with her PhD in May 2017 and has accepted a position at Intel.

Chungwei Lin
Postdoc, Dr. Chungwei Lin
Office: RLM 7.208
Phone: (512) 232-7535
E-mail
About:
Chungwei joined Prof. Demkov.s group in August of 2011. His main interest is combining first-principles calculations and many-body techniques to understand the materials of interest. Chungwei received his Ph.D. in physics from the Columbia University in 2008, where he studied managanite superlattices using the dynamical mean field theory. From 2008-2011 as a postdoc at the University of Pittsburgh, he worked on problems of cold atom systems and on the self-assembly pattern of molecules on metal surface.

Chungwei is currently a researcher at the Mitsubishi Electric Research Laboratories.

Kurt Fredrickson
Graduate Student, Kurt Fredericksen
Office: RLM 7.202
Phone: (512) 232-7573
Website
About:
Kurt Fredrickson arrived at the University of Texas at Austin in Fall 2009 after finishing his B.S. in Physics from the University of California, Davis, and joined the research group of Professor Alex Demkov in the summer of 2010. His current research includes oxide surfaces and heterostructures, with an emphasis on ferroelectric materials. Current and past research includes density functional theory studies of polarization and energy barriers of BaTiO3/Pt superlattices, ferromagnetic and spin-transfer effects in EuO/Pt superstructures, and wetting conditions for BaTiO3/Ge interfaces, with an emphasis on collaboration of theory and experiment.

Kurt is currently working at Applied Materials.

Andy O'Hara
Graduate Student, Andy O'Hara
Office: RLM 7.204
Phone: (512) 232-7588
Website
About:
Andy started at the University of Texas at Austin in the Fall of 2009 after receiving his B. S. in Physics and Mathematics from Haverford College in Pennsylvania. He joined the Demkov group in the Fall of 2010 working on first-principles modeling of novel materials related to the 122 FeAs superconductors and metal-oxide interfaces of importance to reversible dielectric breakdown in ReRAM applications. Some of his current research interests include structural properties and reversible phase transitions in transition metal oxides with potential technological applications.

Andy is currently a post-doc at Vanderbilt University in the group of Sokrates Pantelides.

Matthew Butcher
Undergraduate Student, Matthew Butcher
About:
Matt has been working on research for his senior thesis with the group. His research focus is on the modeling of quantum well structures via the Schrödinger-Poisson equation as applied to transition metal oxide quantum wells.

Matt is currently a graduate student at Rice University.

Miri Choi
Graduate Student, Miri Choi
PhD, 2013
About:
Miri Choi has joined the Physics Department at the University of Texas at Austin as a graduate student in 2008 after receiving her B.S. in Chemistry and MS in physics from the Ewha Womans University in Seoul, Korea. She works on epitaxial growth of oxide-semiconductor heterostructures using molecular beam epitaxy (MBE) and on the characterization and understanding of interface and surface properties in these systems. She is also working on a project to connect the oxide MBE chamber to a low temperature Scanning Tunneling Microscope.

Miri is currently employed at Intel.

Richard Hatch
Postdoc, Dr. Richard Hatch
2012-2014
Website
About:
Richard joined the Materials Physics Lab in August of 2012. He specializes in angle-resolved photoemission spectroscopy (ARPES) experiments to measure electronic band structure, probe formation of electronic properties at interfaces, and study how many-body interactions and broken symmetry environment affect the electronic properties of materials. Richard received his Ph.D. in physics from the University of Wisconsin-Madison in 2010, where he studied organic semiconductors, by using molecular beam epitaxy, synchrotron radiation and ARPES. From 2010 to 2012 he worked as a postdoctoral research fellow at the ASTRID synchrotron in the Department of Physics and Astronomy at Aarhus University in Denmark where he did similar studies on topological insulators and graphene.

Richard is currently working at Orbital ATK, a defense contractor, in Utah.

Haixia Cao
Visiting Researcher, Dr. Haixia Cao (visiting from the Department of Physics, Soochow University, China)
Research:
Electronic structure and magnetism of multiferroic materials using the ab initio pseudopotential density functional theory, giant electrocaloric effect of ferroelectric thin films, as well as dielectric, piezoelectric, pyroelectric and electromechanical properties of functionally graded ferroelectric thin films.

Hosung Seo
Graduate Student, Hosung Seo
PhD, 2013
Research:
First-principles modeling of epitaxial complex oxide heterostructures (e.g. spin state transitions in LaCoO3, anatase TiO2 and CoO on SrTiO3 integrated with Si) as well as simulations of X-ray Core Level Spectroscopy and ARPES

Hosung completed a postdoc at U.C. Davis in 2014 and a second one at Argonne National Lab and the University of Chicago in 2017.
He is currently an Assistant Professor at Ajou University and a Visiting Scholar at the University of Chicago.
Website

Alex Slepko
Graduate Student, Alexander Slepko
PhD, 2013
Masters, 2008
Research:
Silicides, electronic transport (impurity scattering and electron-phonon interactions), biomaterial hydroxyapatite

Currently a Simulations Engineer for Intel.

Chandrima Mitra
Postdoc, Dr. Chandrima Mitra
2010-2013
Research:
Defects in oxides and the structural and physical changes due to their presence.

Currently a Quantitative Analyst at BBVA Compass in the Risk Analytics group.

Lukas Schlipf
Graduate Student, Lukas Schlipf
Masters, 2012
Research:
Thesis on the "Growth and Characterization of the Zintl-phase of SrAl4 on LaAlO3."
Currently researching Nitrogen-Vacancy impurity centers in Diamond at the Max Planck Institute for Solid State Research

Rytis Dargis
Research Associate, Dr. Rytis Dargis
2009-2010

Currently a staff scientist at Translucent, Inc.

Jaekwang Lee
Graduate Student, Jaekwang Lee
Ph.D., 2010
Research:
Physics of Oxide Heterostructures

Currently an Assistant Professor at Pusan National University in Korea.

Xuhui Luo
Graduate Student, Xuhui Luo
Ph.D., 2010
Research:
Structural phase transitions in Hafnia and Zirconia

Currently at CGGVeritas, previously a postdoc at NIST.

Na Sai
Postdoc, Dr. Na Sai
2006-2009
Research

Currently a Postdoc at ICES / Sandia
Office: ACES 4.318
Phone: (512) 232-2397

Onise Sharia
Graduate Student, Onise Sharia
Ph.D., 2008
Research:
The electronic properties of Hafnia interfaces

Currently a Quantitative Financial Analyst at Bank of America.

Manish Niranjan
Graduate Student, Manish Niranjan
Ph.D., 2007
Research:
Theoretical investigation of silicide alloys

Currently an Assistant Professor in the Department of Physics at IIT, Hyderabad

Hendrik Bentmann
Graduate Student, Hendrik Bentmann
MS., 2007
Research:
Properties of PtSi thin films

Currently a postdoc student at Würzburg University

Nikolai Serqueev
Postdoc, Dr. Nikolai Serqueev
2005-2008
Research:
Electron-Phonon interactions and charge transfer in molecular systems

Currently a staff scientist at USC Computational Research & Cyber Infrastructure Support Initiative

Euvgeni Chagarov
Postdoc, Dr. Euvgeni Chagarov
Graduate student at Motorola Labs, Tempe, Arizona 2001-2003

Currently a research scientist in Prof. Andrew C. Kummel's group at the University of California, San Diego

Xiodong Zhang
Postdoc, Dr. Xiaodong Zhang
Postdoc at Motorola Labs, Tempe, Arizona 2000-2002

Currently an Associate Professor in the Department of Radiation Physics at the MD Anderson Cancer Research Center, Houston, Texas as well as at the University of Texas Graduate School of Biomedical Sciences, Houston, Texas. Current website.