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arXiv · 1409.2341

Strain induced edge magnetism at zigzag edge in graphene quantum dot

Shuai Cheng·Jinming Yu·Tianxing Ma·N. M. R. Peres
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Abstract

We study the temperature dependent magnetic susceptibility of a strained graphene quantum dot by using the determinant quantum Monte Carlo method. Within the Hubbard model on a honeycomb lattice, our unbiased numerical results show that a relative small interaction $U$ may lead to a edge ferromagnetic like behavior in the strained graphene quantum dot, and a possible room temperature transition is suggested. Around half filling, the ferromagnetic fluctuations at the zigzag edge is strengthened both markedly by the on-site Coulomb interaction and the strain, especially in low temperature region. The resultant strongly enhanced ferromagnetic like behavior may be important for the development of many applications.

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Shuai Cheng, Jinming Yu, Tianxing Ma, N. M. R. Peres. 2014-09-08. Strain induced edge magnetism at zigzag edge in graphene quantum dot. https://doi.org/10.1103/physrevb.91.075410

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