(a) Schematic depiction of the dispersed-inclusion microstructure. The dashed line delineates a basic structural unit for the composite. (b) Schematic depiction of the symmetric microstructure. Depending on the relative volume fraction of the two components, either component can be the matrix phase.

 Proposed the mechanisms of fluctuation-induced tunneling and structure-correlated hopping that led to the explanation of electrical conduction behaviors in diverse disordered systems such as conducting polymers, carbon-black composites, granular metals, etc.

Key publications:

1. "Hopping Conductivity in Granular Metals", Ping Sheng, B. Abeles and Y. Arie, Phys. Rev. Lett. 31, 44 (1973).
2. "Fluctuation-Induced Tunneling Conduction in Carbon-Polyvinylchloride Composites", Ping Sheng, E. K. Sichel and J. Gittleman, Phys. Rev. Lett. 40, 1197 (1978).
3. "Fluctuation-Induced Tunneling Conduction in Disordered Materials", Ping Sheng, Phys. Rev. B21, 2180 (1980).
4. "Electronic Transport in Granular Metal Films", Ping Sheng, Feature Article, Philos. Mag. B65, 357 (1992).

 Proposed effective medium theories that give microstructure-based explanations to observed optical, electrical, and elastic properties of composites, with granular metals and sedimentary rocks in particular.

Key publications:

1. "Theory for the Dielectric Function of Granular Composite Media", Ping Sheng, Phys. Rev. Lett. 45, 60 (1980).
2. "Effective-Medium Theory of Sedimentary Rocks", Ping Sheng, Phys. Rev. B4l, 4507 (1990).

 Found a two-parameter universal scaling solution for the dynamic (fluid) permeability function in porous media with arbitrary microstructures.

Key publications:

1. "Dynamic Permeability in Porous Media", Ping Sheng and M. Y. Zhou, Phys. Rev. Lett. 61, 1591 (1988).
2. "First-Principles Calculations of Dynamic Permeability in Porous media", M. Y. Zhou and Ping Sheng, Phys. Rev. B39, 12027 (1989).

 Uncovered the bimodal nature of the local field distribution in disordered systems.

Key publication:

"Local-Field Distribution in Random Dielectric Media", Ping Sheng and Z. Chen, Phys. Rev. Lett. 60, 227 (1988).