Dong Yu

Assistant Professor
Department of Physics
University of California at Davis

Office:   Phys/Geo 203
Phone:  530-554-1630
Fax:      530-752-4717
Email:   yu at physics.ucdavis.edu

2008-         Assistant Professor of Physics, University of California at Davis
2005-2008  Postdoc, Harvard University
2000-2005  Ph.D. in Physics, University of Chicago
1995-2000  B.S. in MSE, University of Science and Technology of China
Curriculum Vitae

Group Site


            Quantum Dots                             Nanowires                              Nano-Devices

Research Interest
I am interested in nanoscale physics, particularly, electrical and optical properties of nanowires and nanocrystal quantum dots, and their applications in optoelectronic devices, such as solar cells, photodetectors, light emission diodes, lasers. The current research effort is focused on two directions:

1) Narrow bandgap nanowires for solar cell and electroluminescence applications: One-dimensional quantum confinement is of fundamental interest, and also allows for absorption and emission wavelength tunability. Narrow bandgap materials such as PbS, PbSe and InAs hold large Bohr radii, and thus are attractive candidates to realize strong exciton confinement. Narrow bandgap nanostructures have also received great attention for solar energy conversion for their multiple exciton generation and strong absorption in the infrared range of the solar energy.

2) Transition metal doped nanowires: Introducing even a small quantity of transition metal ions into semiconductors can substantially modify the electrical, magnetic and optical properties of the host materials. The incorporation of transition metal ions into nanostructures may yield even more exciting behaviors, because quantum confinement leads to significant enhancement of this short-range exchange interaction. I am particularly interested in exploring the sp-d interaction through magnetoresistive measurements of single nanowires doped with magnetic ions.

Courses
Spring 2009: PHY 9A-A Classical Mechanics
Fall 2008: PHY 250-02 Introduction to Nanoscale Science

Selected Publications
1.     Yu, D., Brittman, S., Lee, J., Falk, A. L. & Park, H. Minimum voltage for threshold switching in nanoscale phase-change memory. Nano Lett. 8, 3429 (2008).
2.     Lee, J., Brittman, S., Yu, D. & Park, H. Vapor-liquid-solid and vapor-solid growth of phase-change Sb2Te3 nanowires and Sb2Te3/GeTe nanowire heterostructures. J. Am. Chem. Soc. 130, 6252 (2008).
3.     Guyot-Sionnest, P., Yu, D., Jiang, P. H. & Kang, W. Spin blockade in the conduction of colloidal CdSe nanocrystal films. J. Chem. Phys. 127, 014702 (2007).
4.     Yu, D., Wu, J., Gu, Q. & Park, H. Germanium telluride nanowires and nanohelices with memory-switching behavior. J. Am. Chem. Soc. 128, 8148 (2006).
5.     Yu, D., Wehrenberg, B. L., Jha, P., Ma, J. & Guyot-Sionnest, P. Electronic transport of n-type CdSe quantum dot films: Effect of film treatment. J. Appl. Phys. 99, 104315 (2006).
6.     Yu, D., Wehrenberg, B. L., Yang, I., Kang, W. & Guyot-Sionnest, P. Magnetoresistance of n-type quantum dot solids. Appl. Phys. Lett. 88, 072504 (2006).
7.     Guyot-Sionnest, P., Wehrenberg, B. & Yu, D. Intraband relaxation in CdSe nanocrystals and the strong influence of the surface ligands. J. Chem. Phys. 123, 074709 (2005).
8.     Wehrenberg, B. L., Yu, D., Ma, J. S. & Guyot-Sionnest, P. Conduction in charged PbSe nanocrystal films. J. Phys. Chem. B 109, 20192 (2005).
9.     Yu, D., Wang, C. J., Wehrenberg, B. L. & Guyot-Sionnest, P. Variable range hopping conduction in semiconductor nanocrystal solids. Phys. Rev. Lett. 92, 216802 (2004).
10.   Yu, D., Wang, C. & Guyot-Sionnest, P. n-type conducting CdSe nanocrystal solids. Science 300, 1277 (2003).