摘要
本研究采用无符号问题的量子蒙特卡洛模拟，系统研究了一个具有强层间反铁磁交换耦合和局域哈伯德排斥相互作用的双层费米子模型，该模型是实现对称质量生成（SMG）绝缘体的原型。数值精确结果明确表明，在掺杂SMG绝缘体相后，体系中涌现出稳健的超导配对，且哈伯德排斥相互作用显著增强了超导序参量。鉴于该模型可能捕获高压下高温超导体La3Ni2O7的关键特征，此项工作确立了从掺杂SMG母态出发实现超导电性的新范式，为未来实验探索提供了重要理论指导。
材料
方法
- Sign-problem-free quantum Monte Carlo (QMC) simulations
关键词
- symmetric mass generation insulator
- interlayer antiferromagnetic exchange
- superconducting pairing
- hubbard interaction enhancement
- phase stiffness
亮点
- This work establishes a new paradigm for superconductivity arising from a doped SMG parent state and provides key theoretical guidance for future experimental investigations.
- The absence of the sign problem allows for large-scale QMC simulations to explore finite-temperature properties.
结论
- Robust superconducting pairing emerges upon doping the symmetric mass generation (SMG) insulator phase.
- The Hubbard repulsion significantly enhances the superconducting order parameter.
- The superfluid phase stiffness increases rapidly with doping, confirming the superconducting nature of the doped SMG phase.
主要论断
- Robust superconducting pairing emerges upon doping the symmetric mass generation (SMG) insulator phase.
- 证据: Abstract: 'our numerically exact results unambiguously demonstrate that robust superconducting pairing emerges upon doping the SMG phase'
- The Hubbard repulsion significantly enhances the superconducting order parameter.
- 证据: Abstract: 'the SC order is significantly enhanced by the repulsive Hubbard interaction'
研究流程
- Model construction
- 材料: Bilayer fermionic model on square lattice
- 方法: Interlayer Heisenberg exchange; On-site Hubbard interaction
- 观察: Model remains sign-problem-free at arbitrary fillings
- Quantum Monte Carlo simulations — Robust superconductivity arises from doped SMG insulator
- 材料: Model Hamiltonian
- 方法: Sign-problem-free QMC; Calculation of SC structure factor and superfluid stiffness
- 观察: Strong interlayer SC pairing emerges from doped SMG insulator; Hubbard interaction enhances SC