Dr. Stephen Tsui
Dr. Stephen Tsui
Assistant Professor

Office: Science Hall II, Room 217
Phone: (760) 750-4144
Hours: Tuesday 11 am-12 pm and Wednesday 2:30 pm - 3:30 pm
HomeEducationResearchCoursesVitaePublications
Welcome to my little corner of the CSUSM website!

I am an experimental condensed matter physicist with primary interest in electronic conduction phenomena in materials. My research interests span the areas of resistive random access memories, nanoscience, and materials physics.

My teaching responsibilities include both lower and upper division physics courses. Those students pursuing a degree in the Biological Sciences or Biotechnology will likely see me in Physics 205 or 206. Applied Physics Majors will definitely take part in my projects in the Physics 380 and 480 Advanced Laboratories. The structure of our courses benefits greatly from the combined experimental backgrounds of our professors and also the physics education research actively pursued by the Department.

As for my extracurricular pursuits, one of my roles is that of advisor to the CSUSM Chapter of the Society of Physics Students and Sigma Pi Sigma Physics Honor Society. I also perform scientific outreach (usually with a lot of liquid nitrogen!) and participate in various community engagement events.

Feel free to check out the tabs above to see a little more about what I do, or get in touch with me if there is anything that you would like to discuss.  You should also check out the main Physics page for Departmental updates, internships information, and more!

Education

Ph.D. in Physics, University of Houston, 2008
Dissertation: "A carrier hopping mechanism for bipolar field induced resistive switching in metal-Pr0.7Ca0.3MnO3 interfaces"
Advisor, Professor Paul C.W. Chu

M.S in Physics, University of Houston, 2004

B.S. in Physics with Honors, University of Houston, 2002
Honors Thesis: "Development of a straw tracking detector for a new muon to electron conversion experiment"
Advisor, Professor Ed V. Hungerford

Selected Professional Memberships

American Physical Society
Sigma Pi Sigma Physics Honor Society 
CSUSM Asian Pacific Islander Faculty & Staff Association 
Phi Kappa Phi National Honor Society
Golden Key International Honour Society
Alpha Lambda Delta-Phi Eta Sigma Honor Societies 
University of Houston Alumni Association



Research and projects

My background is in experimental condensed matter physics with particular focus in electrical transport characterization. The materials that I have studied include superconductors, semiconductor thin films, and nano-colloidal systems.

My current primary interest is in the field of resistive random access memories. There is a global undertaking to investigate physical phenomena that could lend themselves to higher density nonvolatile memory devices, which hopefully will be superior to the Flash memory in thumb drives, cell phones, and digital cameras. My particular avenue of research is in nonvolatile and reversible reconfiguration of crystalline structures via electric field.

I am also involved with investigations of dielectric behavior in nano-colloidal systems, which are essentially pastes made up of fluid and nanoparticles.  These colloids can be found, for instance, in the field of rheology, which examines the change of fluid viscosity with some externally applied stimulus.  We are presently applying the same experimental techniques to solid nanocomposite systems.

Any student who has an idea that they may want to pursue should feel free to talk to any of the faculty here.  Our students have pursued independent work in STM, piezoelectric sensor arrays, quantum dots, and magnetohydrodynamics.

Lab Group 2013

Undergraduate Researchers 2013.  From left to right: Edgar, Little Eric, Louis, John, and Madison.


Teaching

Physics 101: Introduction to Physics I

First semester introductory course for students without calculus.

Physics 205: Physics for the Biological Sciences I

First semester introductory course for students majoring in biological sciences.  This course is taught in an interactive learning format.

Physics 206: Physics for the Biological Sciences II**

Second semester introductory course for students majoring in biological sciences.  This course is taught in an interactive learning format.

Physics 203: Modern Physics

This is the third semester of our introductory physics sequence for physical science and math students. Topics include thermodynamics and quantum physics.

Physics 380: Advanced Laboratory

Applied Physics students practice experimental techniques, data analysis, scientific writing, and independent experiments.

Physics 422: Applied Solid State Physics**

This course covers topics including crystal structure, elementary band theory, semiconductors, and solid state devices.

** Denotes course being taught this semester.


Positions

Assistant Professor, 2009-present 
Physics Department, California State University San Marcos

Visiting Assistant Professor, 2008-2009 
Physics Department, California State University San Marcos

Adjunct Instructor, 2007
Physical Sciences Department, Houston Community College -- Central Campus

Research Assistant, 2002-2008
Texas Center for Superconductivity, University of Houston


Publications

* denotes CSUSM undergraduate student.

"Suppression of multi-level bipolar resistive switching in Ag/Pr0.7Ca0.3MnO3 interfaces at low temperatures," S. Tsui, C. Salvo*, and M. Lopez*, Journal of Applied Physics 112, 114511 (2012).

"Don't erase that whiteboard! Archiving student work on a photo-sharing website," E. Price, S. Tsui, A. Hart*, and L. Saucedo*, The Physics Teacher 49, 426 (2011).

"Generation of negative capacitance in a nanocolloid," J. Shulman, Y.Y. Xue, S. Tsui, F. Chen, and C.W. Chu, Journal of Applied Physics 109, 034304 (2011).

"Interfacial resistive oxide switch induced by reversible modification of defect structures," S. Tsui, Y.Y. Xue, N. Das, Y.Q. Wang, and C.W.Chu, Physical Review B 80, 165415 (2009).

"General mechanism for negative capacitance phenomena," J. Shulman, Y.Y. Xue, S. Tsui, F. Chen, and C.W. Chu, Physical Review B 80, 134202 (2009).

"Kinetics and relaxation of electroresistance in transition metal oxides: model for resistive switching," N. Das, S. Tsui, Y.Y. Xue, Y.Q. Wang, and C.W. Chu, Physical Review B 80, 115411 (2009).

"Electric-field-induced submicrosecond resistive switching," N. Das, S. Tsui, Y.Y. Xue, Y.Q. Wang, and C.W. Chu, Physical Review B 78, 235418 (2008).

"Plasmalike negative capacitance in nanocolloids," J. Shulman, S. Tsui, F. Chen, Y.Y. Xue, and C.W. Chu, Applied Physics Letters 90, 32902 (2007).

"Mechanism and scalability in resistive switching of metal-Pr0.7Ca0.3MnO3 interface," S. Tsui, Y.Q. Wang, Y.Y. Xue, and C.W. Chu, Applied Physics Letters 89, 123502 (2006).

"Field-induced giant static dielectric constant in nano-particle aggregates at room temperature," F.Chen, J. Shulman, S. Tsui, Y.Y. Xue, W. Wen, P.Sheng, and C.W. Chu, Philosophical Magazine 86, 2393 (2006).

"A negative dielectric constant in nano-particle materials under an electric field at very low frequencies," C.W. Chu, F. Chen, J. Shulman, S. Tsui, Y.Y. Xue, W. Wen, and P. Sheng, Proceedings of the SPIE 5932, 139 (2005).

"Field-induced resistive switching in metal-oxide interfaces," S. Tsui, A. Baikalov, J. Cmaidalka, Y.Y. Sun, Y.Q. Wang, Y.Y. Xue, C.W. Chu, L. Chen, and A.J. Jacobson, Applied Physics Letters 85, 317 (2004).

"Field-driven hysteretic and reversible resistive switch at the Ag-Pr0.7Ca0.3MnO3 interface," A. Baikalov, Y.Q. Wang, B. Shen, B. Lorenz, S. Tsui, Y.Y. Sun, Y.Y. Xue, and C.W. Chu, Applied Physics Letters 83, 957 (2003).

"Crypto-superconductivity in RuSr2GdCu2O8," Y.Y. Xue, S. Tsui, J. Cmaidalka, R.L. Meng, B. Lorenz, and C.W. Chu, Physica C: Superconductivity 341-348, 483 (2000).

"A possible crypto-superconducting structure in a superconducting ferromagnet," C.W. Chu, Y.Y. Xue, S. Tsui, J. Cmaidalka, A.K. Heilman, B. Lorenz, and R.L. Meng, Physica C: Superconductivity 335, 231 (2000).