Lawrence Lehman

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—Digital image correlation and cross polarizer, optical microscopy were used to quantify the deformation behavior under deep thermal cycling of near eutectic SnAgCu (SAC) solder in board level interconnects. Maps with sub micron spatial resolution of the strain levels and von Mises strain were produced for selected cross sections. Large spatial variations(More)
Optical microscopy was used to discern the different grain orientations and grain boundaries on the polished cross-sections of near-eutectic lead-free board-level SnAgCu (SAC) solder interconnects. Strain distributions with submicron accuracy of the deformations on the cross-sections of the solder interconnects were measured when the package was subjected(More)
We analyze the low energy excitations of spin lattice systems in two dimensions at zero temperature within the framework of projected entangled pair state models. Perturbations in the bulk give rise to physical excitations located at the edge. We identify the corresponding degrees of freedom, give a procedure to derive the edge Hamiltonian, and illustrate(More)
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