The jamming of bi-disperse soft core disks is considered, using a variety ofdifferent protocols to produce the jammed state. In agreement with other works,we find that cooling and compression can lead to a broad range of jammingpacking fractions $\phi_J$, depending on cooling rate and initialconfiguration; the larger the degree of big particle clustering in the initialconfiguration, the larger will be the value of $\phi_J$. In contrast, we findthat shearing disrupts particle clustering, leading to a much narrower range of$\phi_J$ as the shear strain rate varies. In the limit of vanishingly smallshear strain rate, we find a unique non-trivial value for the jamming densitythat is independent of the initial system configuration. We conclude that sheardriven jamming is a unique and well defined critical point in the space ofshear driven steady states. We clarify the relation between glassy behavior,rigidity and jamming in such systems and relate our results to recentexperiments.
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