Andrew Zangwill
Professor

 

Ph.D., University of Pennsylvania, 1981
Phone: (404)894-7333
Room: Howey-N102

EMail: andrew.zangwill [at] physics.gatech.edu

 

■ Bio Info ■

Andrew Zangwill was born in Pittsburgh, PA in 1954. He graduated from the Junior Space Academy of the Buhl Planetarium in 1964 and received his BS in Physics in 1976 from Carnegie-Mellon University. Five years later, he earned his PhD in Physics from the University of Pennsylvania. Following a post-doctoral stint at Brookhaven National Laboratory, he began his academic career as an Assistant Professor at the Polytechnic Institute of Brooklyn. He moved to Georgia Tech in 1985 as an Associate Professor, where he is now Professor of Physics and Associate Chair for Graduate Affairs. Zangwill is a Fellow of the American Physical Society.

■ Research ■

Professor Zangwill's theoretical research program focuses on some of the physics issues that arise when semiconductor and magnetic systems shrink to the nanoscale.

One strand of this research is devoted to understanding the phenomenon of epitaxial growth. Long regarded as an art rather than a science, there is now an urgent need to establish predictive models for the growth of "designer" crystals that are synthesized one atom at a time. Interest in this question extends far beyond the limited concerns of the crystal grower because the epitaxial growth process is a paradigm of a driven, non-equilibrium process - a subject of considerable interest to the condensed matter community as a whole.

The ideal scenario for perfect single crystal growth is to repeatedly deposit exactly one monolayer of atoms. Unfortunately, the usual experimental situation is that multilevel roughness develops as growth proceeds. To study such behavior, we have been using kinetic Monte Carlo simulations and stochastic, non-linear partial differential equations to model the growing surface. A challenging new direction for this research combines these statistical methods with continuum elasticty theory in order to understand the spontaneous creation of semiconductor quantum dots when, say, Ge is grown on Si or InAs is grown on GaAs.

Another aspect of our research focuses on magnetic nanostructures. Here, our main interest is to understand the non-equilibrium phenomenon of hysteresis in ultra-thin magnetic films. Through the use of large-scale spin simulations and analytic calculations, we have established the fundamental origin of coercivity in these systems and the role they play in practical devices such as giant magnetoresistance read heads.

Hysteresis in nanostructures is determined largely by their magnetic anisotropy-a fundamental consequence of the spin orbit interaction in solids. Our recent work in this area has been devoted to discovering the origin of magnetic anisotropy in these systems through the use of first-principles electronic structure calculations.

■ Publications ■

1. “Macrospin Models of Spin-Transfer Dynamics, J. Xiao, A. Zangwill, and M.D. Stiles, Physical Review B 72, 014446 (2005).
2. “Boltzmann test of Slonczewski's theory of spin-transfer torque”, J. Xiao, A. Zangwill, and M.D.Stiles, Physical Review B 70, 172405 (2004).
3. “Phenomenological Theory of Current-Induced Magnetization Precession”, M.D.Stiles, J. Xiao, and A. Zangwill, Physical Review B 69, 054408 (2004).
4. “Homoepitaxial Ostwald Ripening”, M. Petersen, Ch. Ratsch, and A. Zangwill, Surface Science, 536, 55 (2003).
5. “Electrostatics of Conducting Nanotubes”, M. Krcmar, W.M. Saslow, and A. Zangwill, J. of Applied Physics 93, 3495 (2003).
6. “Static Screening by Conducting Nanospheres”, M. Krcmar, W.M. Saslow, and A. Zangwill, J. of Applied Physics 93, 3490 (2003).
7. “Non-Collinear Spin Transfer in Co/Cu/Co Multilayers”, M. Stiles and A. Zangwill, J. Appl. Phys. 91, 6812 (2002).
8. “Anatomy of Spin-Transfer Torque”, M. Stiles and A. Zangwill, Phys. Rev. B 66, 014407 (2002).
9. “Interpretation of Resonant Photoemission Spectra of Solid Actinide Systems”, S. L. Molodtsov, S. V. Halilov, M. Richter, A. Zangwill, and C. Laubscat, Physical Review Letters 87, 017601 (2001).
10. “Spin-Other-Orbit Interaction and Magnetocrystalline Anisotropy”, M. D. Stiles, S. V. Halilov, R. A. Hyman, and A. Zangwill, Physical Review B 64, 104430 (2001).
11. “Convective Instability of Strained Step-Flow Growth”, N. Israeli, D. Kandel, M. Schatz, and A. Zangwill, Surface Science 494, L735 (2001).
12. “Level Set Approach to Reversible Epitaxial Growth”, M. Petersen, C. Ratsch, R. Caflisch, and A. Zangwill, Physical Review E 64 61602 (2001).
13. “Capacitance of a Thomas-Fermi Nanosphere”, M. Kremar, W. Saslow, and A. Zangwill, Applied Physics Letters 77, 3797 (2000).
    “Gradient Search Method for Density Functional Calculations”, R. A. Hyman, M. D. Stiles, and A. Zangwill, Physical Review B 62, 15521 (2000).
14.  Click for More Prof. Zangwill's Publications