The one-dimensional t(1)-t(2)-J(1)-J(2) model is examined in the one-hole and two-hole cases. The ground-state phase diagram of the one-hole case includes a series of partial ferromagnetic phases, which are stacked in a regime of positive and small J(1). The ground state in each of these partial ferromagnetic phases includes a ferromagnetic cloud, which is a multiple-spin bound state together with the hole. The ferromagnetic cloud is a large magnetic polaron with a heavy mass in a single-band electronic system and is considered to form as a result of Nagaoka ferromagnetism, which locally acts around the hole. Results for the two-hole case suggest the existence of a liquid of ferromagnetic clouds at a finite hole density.
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