Carsten Ullrich
Associate Professor of Physics
UMC
 		   Carsten Ullrich    
Office:  424 Physics Building
Phone: 573-882-2467
E-mail: ullrichc@missouri.edu
Webpage: http://web.missouri.edu/~ullrichc
Biographical Information: Ph.D., Universitat Wurzburg, Germany 1995


Research Interests

Condensed Matter Theory
Semiconductor Charge and Spin Dynamics

Our main area of research is time-dependent density-functional theory (TDDFT). This theory is the generalization of the well-known ground-state density-functional theory (Walter Kohn, Nobel Prize 1998) and allows one to describe the dynamics of interacting electron systems. I am interested in the formal aspects of TDDFT, such as non-adiabatic behavior and memory effects, as well as in various applications in the linear-response regime and for nonlinear, strongly driven systems. Most of our computational applications deal with semiconductor nanostructures, but we also study atoms and metal clusters in strong fields:
  • Intersubband charge- and spin-density excitations in semiconductor quantum wells, including disorder and spin-orbit coupling;
  • Nonlinear intersubband terahertz dynamics and coherent control in strongly driven quantum wells;
  • Collective excitations of quantum dots in magnetic fields;
  • Nonlinear electron dynamics in atoms and metal clusters driven by strong laser fields: harmonic generation, multiphoton ionization and above-threshold ionization.
Another research area deals with charge and spin transport in diluted magnetic semiconductors. These materials are of interest in the search for spintronics devices and applications. Our specific interest lies in the development of a theory to describe scattering off magnetic impurities, in the case of strongly disordered systems. The goal is to describe optical and transport properties of transition-metal doped semiconductors such as (Ga,Mn)As.

Selected Publications
  1. Excitation energies from time-dependent density-functional theory beyond the adiabatic approximation
    C. A. Ullrich and K. Burke, J. Chem. Phys. 121, 28 (2004) (link)
  2. Coherent control of intersubband optical bistability in quantum wells
    H. O. Wijewardane and C. A. Ullrich, Appl. Phys. Lett. 84, 3984 (2004) (link)
  3. Anisotropic splitting of intersubband spin plasmons in quantum wells with bulk and structural inversion asymmetry
    C. A. Ullrich and M. E. Flatte, Phys. Rev. B 68, 235310 (2003) (link)
  4. Intersubband spin-density excitations in quantum wells with Rashba spin splitting
    C. A. Ullrich and M. E. Flatte, Phys. Rev. B 66, 205305 (2002) (link)
  5. Degeneracy in density functional theory: topology in the v and n spaces
    C. A. Ullrich and W. Kohn, Phys. Rev. Lett. 89, 156401 (2002) (link)
  6. Time-dependent current density functional theory for the linear response of weakly disordered systems
    C. A. Ullrich and G. Vignale, Phys. Rev. B 65, 245102 (2002) (link)
  7. Kohn-Sham theory for ground-state ensembles
    C. A. Ullrich and W. Kohn, Phys. Rev. Lett. 87, 093001 (2001) (link)
  8. Theory of the linewidth of intersubband plasmons in quantum wells
    C. A. Ullrich and G. Vignale, Phys. Rev. Lett. 87, 037402 (2001) (link)
  9. Nonlinear electron dynamics in metal clusters
    F. Calvayrac, P.-G. Reinhard, E. Suraud, and C. A. Ullrich, Phys. Rep. 337, 493 (2000) (link)
  10. Collective charge-density excitations of non-circular quantum dots in a magnetic field
    C. A. Ullrich and G. Vignale, Phys. Rev. B 61, 2729 (2000) (link)
  11. Time-dependent density functional theory beyond the adiabatic local density approximation
    G. Vignale, C. A. Ullrich, and S. Conti, Phys. Rev. Lett. 79, 4878 (1997) (link)
  12. Metallic clusters in strong femtosecond laser pulses
    C. A. Ullrich, P.-G. Reinhard, and E. Suraud, J. Phys. B: At. Mol. Opt. Phys. 30, 5043 (1997) (link)
  13. Many-electron atoms in strong femto-second laser pulses: a density-functional study
    C. A. Ullrich and E. K. U. Gross, Comments At. Mol. Phys. 33, 211 (1997)
  14. Time-dependent optimized effective potential
    C. A. Ullrich, U. J. Gossmann, and E. K. U. Gross, Phys. Rev. Lett. 74 , 872 (1995) (link)