Allan H. MacDonald
Allan H. MacDonald is a theoretical condensed matter physicist and the Sid W. Richardson Foundation Regents Chair Professor of Physics at The University of Texas at Austin. His research interests are centered on the electronic properties of electrons in metals and semiconductors. He is well known for his work on correlated many-electron states in low-dimensional systems. In 2020, he became one of the laureates of the Wolf Prize in Physics, for predicting the magic angle that turns twisted bilayer graphene into a superconductor.
Education and early life
He was born in Antigonish, Nova Scotia, Canada, and attended local schools completing a B.S. at St. Francis Xavier University in 1973. He completed his Ph.D.in physics at the University of Toronto in 1978, working with S.H. Vosko on relativistic generalizations of density functional theory, and on the application of density functional theory to magnetism in metals.Research and career
Prior to joining the University of Texas, he worked at the Ottawa laboratory of the National Research Council Canada and at Indiana University. He has held visiting positions at the Swiss Federal Institute of Technology in Zurich and the Max Planck Institute for Solid State Research in Stuttgart, Germany.MacDonald's research has focused on new or unexplained phenomena related to the quantum physics of interacting electrons in materials. He has contributed to theories of the integer and fractional quantum Hall effects, spintronics in metals and semiconductors, topological Bloch bands and momentum-space Berry curvature phenomena, correlated electron-hole fluids and exciton and polariton condensates, and two-dimensional materials.
In 2011 MacDonald and Rafi Bistritzer, a former postdoctoral researcher in MacDonald's lab, predicted that it would be possible to realize strong correlation physics in graphene bilayers twisted to a magic relative orientation angle, foreshadowing the field of twistronics. Pablo Jarillo-Herrero, an experimentalist at Massachusetts Institute of Technology, found that the magic angle resulted in the unusual electrical properties the UT Austin scientists had predicted. At 1.1 degrees rotation at sufficiently low temperatures, electrons move from one layer to the other, creating a lattice and the phenomenon of superconductivity. The magic angle allows electric current to pass unimpeded, apparently without energy loss. This discovery could lead to more efficient electrical power transmission or new materials for quantum applications.
His recent work is focused on anticipating new physics in moiré superlattices, and on achieving a full understanding of magic-angle bilayer graphene and transition-metal dichalcogenide moiré superlattice systems.