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Vincenzo Vitelli

Postdoctoral Fellow


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My research interests are in the areas of condensed matter theory and statistical mechanics with an emphasis, over the last few years, on the physics of frustrated and amorphous materials. I have contributed to elucidate the properties of crystalline, liquid crystalline and He films confined on in-homogeneously curved substrates. Current work is addressing energy transport and vibrational dynamics in jammed packings of soft spheres just above the onset of mechanical rigidity. These simple models offer insights into the physics of granular materials and glasses.

Below you find more details on two problems that I am currently investigating:

Geometric Theory of Columnar Order on Curved Surfaces

(with C.D. Santangelo, R. D. Kamien and D. R. Nelson)

We study geometrically frustrated systems composed by thin self-assembled columns such as the ones generated in block-copolymer systems. In the limit of vanishing compressional strain, the normals to the columns converge (diverge) in regions of positive (negative) Gaussian curvature, in analogy to the focusing of light rays by a lens. This simple observation is the basis for a versatile analytical approach that we have developed to calculate the geometric interaction between dislocations and Gaussian curvature in columnar as well as crystalline monolayers. The resulting geometrical forces play an important role in stress relaxation dynamics, elastic instabilities, and melting. Please click here for our paper and poster.

Energy Transport in Model Jammed Systems

(with N. Xu, M. Wyart, A. J. Liu, S. R. Nagel)

We generate computer models of jammed packings and calculate their energy diffusivity, a spectral measure of transport that controls both sound attenuation and thermal conductivity. The diffusivity of an isostatic packing is low and nearly constant without any hint of the common divergence associated with long wavelength phonons which are replaced in this system by extended and poorly conducting modes. At higher packing fractions, plane wave-like states coexist with the resonant modes localized in soft portions of the sample and characterized by divergent Gruneisen parameters. Please click here for slides of a recent talk and a sound-bite.