Department of Physics

nsm > physics > faculty > kyeongjae cho

Kyeongjae (KJ) Cho , Ph.D.

Education

• BS in Physics (1986), Seoul National University, Korea
• MS in Physics (1988), Seoul National University, Korea
• Ph.D. in Physics (1994), Massachusetts Institute of Technology
• Postdoctoral Associate (1994-1995), Massachusetts Institute of Technology
• Postdoctoral Associate (1995-1996), Harvard University

Overview

Dr. Cho is an Associate Professor of Physics and Electrical Engineering (Materials Science and Engineering Program). Before joining UT Dallas in 2006, Dr. Cho was an Assistant Professor of Mechanical Engineering and Materials Science and Engineering at Stanford University.

Dr. Cho’s research interest is computational modeling study of nanomaterials with applications to nanoelectronic devices and renewable energy technology. For materials modeling study, his research group has developed atomistic modeling method to simulate atomic structures of nanomaterials and tight binding method to calculate electronic structures and quantum transport properties of nanoelectronic devices. Advanced first principles quantum simulations methods (density functional theory) are used to investigate the nanomaterials with quantitative accuracy and fundamental understanding of structure-property relationship.

Research Interests

Nanomaterials for renewable energy application: Limited supply of fossil fuels and environmental pollution issues require renewable energy technology using hydrogen as energy carriers. Three key technology components are hydrogen production, storage, and utilization in fuel cells. At the core of the renewable energy technology research is new materials to convert energy from one form to another (e.g., photon energy to electricity in solar cell, or chemical energy to electricity in fuel cell). There are extensive research efforts to develop new nanomaterials with higher efficiency in the energy conversion and optimized functional properties, but most of them are driven by empirical trial-and-error material development process. Computational modeling can provide detailed understanding on the microscopic mechanisms and properties nanomaterials for diverse applications. Our research is to apply molecular dynamics and Monte Carlo simulations to identify atomic structures of nanoscale materials and use quantum simulations to investigate functional properties through electronic structure analysis. Target materials systems are carbon nanotubes, semiconductor nanowires, metal nanoparticles, and oxide nanomaterials in diverse functional nanocomposite nanomaterials.

High-k gate stack technology: Device scaling is leading to sub 32nm device feature size and continuous scaling requires new device materials such as high-k gate dielectric (replacing silica), metal gate electrode (replacing doped poly-silicon), and high mobility channel materials (e.g., Ge or compound semiconductors replacing silicon). These new device materials form interfaces and the interface properties critically control the device performance. These interfaces are very thin (nm scale), and computational modeling can provide critical insight to solve many technological challenges in developing the high-k gate stack as future device technology. Our research will apply atomistic modeling method to determine the atomic structure of the interfaces and quantum mechanical simulations to calculate the electronic structures. The analysis of simulation results would provide detailed insights on the nano-scale structure-property relationship of high-k gate stack materials.

Selected Publications

1. P. Leu, B. Shan, and K. Cho, “Surface chemical control of the electronic structure of silicon nanowires: Density functional calculations,” Phys. Rev. B 73, 195320 (2006).
2. B. Lee and K. Cho, “Extended embedded-atom method for platinum nanoparticles,” Surf. Sci. 600, 1982 (2006).
3. B. Shan and K. Cho, “First Principles Study of Work Functions of Double Wall Carbon Nanotubes,” Phys. Rev. B 73, 081401(R) (2006).
4. S. Park, L. Colombo, Y. Nishi, and K. Cho, “Ab initio Study of Metal Gate Electrode Work Function,” Appl. Phys. Lett. 86, 73118 (2005).
5. B. Shan and K. Cho, “First Principles Study of Work Functions of Single Wall Carbon Nanotubes,” Phys. Rev. Lett. 94, 236602 (2005).
6. B. Shan, G. Lakatos, S. Peng and K. Cho, “First Principles Study of band-gap change in deformed nanotubes,” Appl. Phys. Lett. 87, 173109 (2005).
7. H.J. Liu and K. Cho, “A molecular dynamics study of round and flattened carbon nanotube structures,” Appl. Phys. Lett. 85, 807 (2004).
8. S. Peng, K. Cho, P. Qi, and H. Dai, “Ab initio Study of CNT NO2 gas sensor,” Chem. Phys. Lett. V.387 p.271-276 (2004).
9. P. Ramanarayanan, K. Cho, B.M. Clemens, “Effect of composition on vacancy mediated diffusion in random binary alloys: First principles study of the Si1-xGex system,” J. Appl. Phys. v.94, no.1, p.174-185 (2003).
10. A. Nojeh, G.W. Lakatos, S. Peng, K. Cho, and R.F.W. Pease, “A Carbon Nanotube Cross Structure as a Nanoscale Quantum Device,” Nano Lett. v.3, no.9, p.1187-1190 (2003).
11. S. Park, D. Srivastava, and K. Cho, “Generalized Chemical Reactivity of Curved Surfaces: Carbon Nanotubes,” Nano Lett. v.3, no.9, p.1273-1277 (2003).
12. S. Peng and K.Cho, “Ab Initio Study of Doped Carbon Nanotube Sensors,” Nano Lett. 3(4), 513-517 (2003).
13. S. Peng and K. Cho, “Nano Electro Mechanics of Semiconducting Carbon Nanotube,” J. Appl. Mech. v.69, no.4, p.451-453 (2002).
14. J. O’Keeffe, C. Wei, and K. Cho, “Band-structure modulation for carbon nanotubes in a uniform electric field,” Appl. Phys. Lett. 80, 676-678 (2002).
15. A. Kawamoto, K. Cho, P. Griffin, and R. Dutton, “First Principles Investigation of Scaling Trends of Zirconium Silicate Interface Band Offsets,” J. Appl. Phys. 90, 1333 (2001).
16. S. Park, D. Srivastava, and K. Cho, “Local reactivity of fullerenes and nano device design,” Nanotechnology 12, 245 (2001).

Number of US Patents Issued and Applied: 6

• Updated: January 16, 2007