Principal Investigator Mingda Li
Project Website http://engnano.mit.edu/
The group, a combined theoretical and experimental group at MIT Nuclear Science and Engineering department, studies the influence of materials' defects on energy transport and conversion processes at nanoscale, using unrestricted methods ranging from quantum field theory to sample growth.
Defects are ubiquitous in materials. Despite the deceptive name “defects”, they have far-reaching significance to energy materials beyond degradation, from improved mechanical properties in metals to enhanced energy conversion efficiency in waste heat recovery, from driving classical and quantum phase transitions to functional properties in nanomaterials. We can even say that understanding defects are like having a set of whole new dimensions for materials improvement.
However, the vast opportunities associated with defects come with a price: the extreme complexity. Even for 0D point defects there are already different types (vacancies, interstitials and substitutions), not to mention the extended defects, such as 1D line defects (dislocations and disclinations), 2D planar defects (interfaces, surfaces, grain boundaries, twin boundaries, stacking faults etc.) and 3D bulk defects (voids, precipitates, inclusions etc.). Each single type of defect can cause profound change to materials. To see the difficulty, even the resistance R=V/I in a dislocated crystal is still not possible to be computed microscopically from first principles: