Theoretical study on three-component repulsive fermionic atoms in optical lattices as quantum simulator

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K05232
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Atomic/Molecular/Quantum electronics
• Research Institution: University of Hyogo
• Principal Investigator: Seiichiro Suga 兵庫県立大学, 工学研究科, 教授 (40206389)
• Research Collaborator: Yamada Takuto
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 量子シミュレータ / 3成分斥力フェルミ原子 / 光格子 / 斥力誘起s波超流動 / キタエフスピン液体 / マヨラナフェルミ粒子

Outline of Final Research Achievements

We have investigated the Cooper pairing symmetry of the superfluid state in three-component repulsive fermionic atoms in optical lattices. We have found that when two repulsions are stronger (weaker) than the other, the pairing symmetry is an extended s wave (a d_{x2-y2} wave). The results suggest that three-component 6Li atoms in optical lattices act as quantum simulator that can control the Cooper pairing symmetry. The results are also important to reveal the origin of the s-wave superconductivity in U-based materials. Next, we have investigated Kitaev-Heisenberg model on honeycomb lattices, and have found that nontrivial behavior originating from Majorana fermions emerges in magnetically ordered phase close to the Kitaev spin liquid (KLS) phase. We have further proposed an effective model for a KSL-material RuCl3, and have succeeded in explaining the unresolved experimental results for inelastic neutron scattering and specific heat not only qualitatively but also quantitatively.

Free Research Field

物性理論