Ordered droplets in quantum magnets with long-range interactions
نویسندگان
چکیده
A defect coupling to the square of the order parameter in a nearly quantum-critical magnet can nucleate an ordered droplet while the bulk system is in the paramagnetic phase. We study the influence of long-range spatial interactions of the form r on the droplet formation. To this end, we solve a Landau-Ginzburg-Wilson free energy in saddle point approximation. The longrange interaction causes the droplet to develop an energetically unfavorable power-law tail. However, for σ > 0, the free energy contribution of this tail is subleading in the limit of large droplets; and the droplet formation is controlled by the defect bulk. Thus, for large defects, long-range interactions do not hinder the formation of droplets.
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