AI 中文总结
研究通过大规模密度矩阵重整化群，在棋盘格t-J模型中研究掺杂反铁磁莫特绝缘体，绘制基态相图，发现从均匀d波超导到PDW态的转变及非常规波矢锁定，揭示对关联双尺度结构并分析，确定反铁磁性是有限动量超导的途径。
AI 中文摘要
对密度波（PDW）超导是一种超导序参量在有限波矢处调制的状态。我们使用大规模密度矩阵重整化群，研究棋盘格t-J模型中的掺杂反铁磁莫特绝缘体，其中反铁磁交换各向异性通过各向异性铁磁次近邻交换微观编码。通过绘制作为掺杂和反铁磁各向异性函数的基态相图，主要在六腿圆柱上，我们确定了从具有电荷调制的均匀d波超导态到与条纹序共存的PDW态的转变。在PDW态中，我们报告了沿圆柱方向的非常规波矢锁定Q_PDW≈2Q_Stripe，与传统关系不同。对关联揭示了一种双尺度结构，由短程局域d波配对和长程有限动量PDW关联组成。我们对观察到的锁定进行了基于对称性的金兹堡-朗道分析。我们的结果表明反铁磁性是掺杂莫特绝缘体中有限动量超导的强耦合、微观基础途径。
英文摘要
Pair-density-wave (PDW) superconductivity is a state in which the superconducting order parameter modulates at a finite wavevector. Using large-scale density matrix renormalization group, we study the doped altermagnetic Mott insulator in the checkerboard $t$-$J$ model, where altermagnetic exchange anisotropy is encoded microscopically through anisotropic ferromagnetic next-nearest-neighbor exchange. By mapping the ground-state phase diagram as a function of doping and altermagnetic anisotropy, mainly on six-leg cylinders, we identify a transition from a uniform $d$-wave superconducting regime with charge modulation to a PDW regime coexisting with stripe order. In the PDW regime, we report an unconventional wave-vector locking $\mathbf Q_{\mathrm{PDW}}\approx 2\mathbf Q_{\mathrm{Stripe}}$ along the cylinder direction, in contrast to the conventional relation. Pair correlations reveal a two-scale structure, consisting of short-distance local $d$-wave pairing and long-distance finite-momentum PDW correlations. A symmetry-based Ginzburg--Landau analysis is presented for the observed locking. Our results identify altermagnetism as a strong-coupling, microscopically grounded route to finite-momentum superconductivity in doped Mott insulators.
Comments5 pages; 4 figures
