- 著者
- Hamamoto Yuji Kawarabayashi Tohru Aoki Hideo Hatsugai Yasuhiro
- 出版者
- American Physical Society
- 雑誌
- Physical review B (ISSN:10980121)
- 巻号頁・発行日
- vol.88, no.19, pp.195141, 2013-11
- 被引用文献数
- 2 1
Motivated by the recent experiments indicating a spin-unpolarized ν=0 quantum Hall state in graphene, we theoretically investigate the ground state based on the many-body problem projected onto the n=0 Landau level. For an effective model with the on-site Coulomb repulsion and antiferromagnetic exchange couplings, we show that the ground state is a doubly degenerate spin-resolved chiral condensate in which all the zero-energy states with up spin are condensed into one chirality, while those with down spin to the other. This can be exactly shown for an Ising-type exchange interaction. The charge gap due to the on-site repulsion in the ground state is shown to grow linearly with the magnetic field, in qualitative agreement with the experiments.