Chiang elected Academician of the Academia Sinica

Siv Schwink

Emeritus and Research Professor of Physics Tai-Chang Chiang, University of Illinois at Urbana-Champaign
Emeritus and Research Professor of Physics Tai-Chang Chiang, University of Illinois at Urbana-Champaign
Emeritus and Research Professor Tai-Chang Chiang of the University of Illinois at Urbana-Champaign has been elected by the Academia Sinica to its 2016 class of Academicians. He is among 22 scholars across all academic disciplines to receive this high honor this year. Academia Sinica is the national academy of Taiwan. Former Academicians in the mathematics and physics division include Nobel laureates T.D. Lee, C.N. Yang, Sam Ting, and Daniel Tsui.

Over the course of his career, Chiang has made lasting contributions to condensed matter physics, surface science, and synchrotron radiation research, including several truly groundbreaking findings. He has authored about 300 journal articles, and his work has been cited more than 8,500 times.

Chiang’s work on precision electron spectroscopy and structural determination has led to important advances in the physics of electrons, lattice structures, and phonons and their mutual interactions in solids, at surfaces, in films, and at the nanoscale.

His landmark research on thin films and quantum well spectroscopy has received international recognition. Specifically, Chiang showed that quantum well states could be observed in films as thick as tens of atomic layers, debunking the notion that only semiconductor substrates could support quantum well states.

Another important breakthrough for Chiang was the making of atomically uniform films for thicknesses over a hundred atomic layers. This work again received international attention. Chiang went on to elucidate the properties of the surface, bulk, quantum well, multilayer, and superlattice electronic states. The accumulated work is a tour-de-force demonstration of quantum-state control through nanoscale engineering of film structures.

Chiang has since broadened his work to include ultrathin films of 3D topological materials, with a focus on the topological properties in the thin film (2D) limit.

Chiang is the recipient of numerous recognitions, including the 2015 Davisson-Germer Prize in Atomic or Surface Physics, sponsored by the American Physical Society (APS). He received the Xerox Award for Faculty Research (1985), the NSF Presidential Young Investigator Award (1984-89), and the IBM Faculty Development Award (1984-5). He is a Fellow of the APS.

Chiang’s professional service is likewise noteworthy. He served as head of the Solid State Sciences and Materials Chemistry Program from 1991 to 2006. He was associate director of the Frederick Seitz Materials Research Laboratory from 1999 to 2006. From 2003 to 2008, he chaired the Board of Governors for UNICAT at the Advanced Photon Source, Argonne National Laboratory. From 2010 to 2014, he served as the scientific director of the University of Wisconsin-Madison Synchrotron Radiation Center. He was appointed Chair Professor at the National Chiao-Tung University (2013-16); Honorary Chair at National Tsing Hua University (2008-11); and Distinguished Chair at National Taiwan University (2007-10 and 2015-present). He is currently a visiting professor at Tokyo University.

Chiang received a bachelor’s degree in physics from the National Taiwan University in 1971 and a doctoral degree in physics from the University of California, Berkeley in 1978. He held a postdoctoral appointment at the IBM T.J. Watson Research Center in Yorktown Heights from 1978 to 1980, before he joined the faculty at Physics Illinois in 1980.

Recent News

  • Research
  • Condensed Matter Theory

We analyze the interplay between a d-wave uniform superconducting and a pair-density-wave (PDW) order parameter in the neighborhood of a vortex. We develop a phenomenological nonlinear sigma model, solve the saddle-point equation for the order-parameter configuration, and compute the resulting local density of states in the vortex halo. The intertwining of the two superconducting orders leads to a charge density modulation with the same periodicity as the PDW, which is twice the period of the charge density wave that arises as a second harmonic of the PDW itself. We discuss key features of the charge density modulation that can be directly compared with recent results from scanning tunneling microscopy and speculate on the role PDW order may play in the global phase diagram of the hole-doped cuprates.

  • Research
  • Condensed Matter Physics

Now, a novel sample-growing technique developed at the U. of I. has overcome these obstacles. Developed by physics professor James Eckstein in collaboration with physics professor Tai-Chang Chiang, the new “flip-chip” TI/SC sample-growing technique allowed the scientists to produce layered thin-films of the well-studied TI bismuth selenide on top of the prototypical SC niobium—despite their incompatible crystalline lattice structures and the highly reactive nature of niobium.

These two materials taken together are ideal for probing fundamental aspects of the TI/SC physics, according to Chiang: “This is arguably the simplest example of a TI/SC in terms of the electronic and chemical structures. And the SC we used has the highest transition temperature among all elements in the periodic table, which makes the physics more accessible. This is really ideal; it provides a simpler, more accessible basis for exploring the basics of topological superconductivity,” Chiang comments.