Charge stripe manipulation of superconducting pairing symmetry transition

Charge stripes have been widely observed in many different types of unconventional superconductors, holding varying periods (P) and intensities. However, a general understanding on the interplay between charge stripes and superconducting properties is still incomplete. Here, using large-scale unbiased numerical simulations on a general inhomogeneous Hubbard model, we discover that the charge-stripe period P, which is variable in different real material systems, could dictate the pairing symmetries—d wave for P ≥ 4, s and d waves for P ≤ 3. In the latter, tuning hole doping and charge-stripe amplitude can trigger a d−s wave transition and magnetic-correlation shift, where the d-wave state converts to a pairing-density wave state, competing with the s wave. These interesting phenomena arise from an unusual stripe-induced selection rule of pairing symmetries around on-stripe region and within inter-stripe region, giving rise to a critical point of P = 3 for the phase transition. In general, our findings offer important insights into the differences in the superconducting pairing mechanisms across many P-dependent superconducting systems, highlighting the decisive role of charge stripe.

Chao Chen, Peigeng Zhong, Xuelei Sui, Runyu Ma, Ying Liang, Shijie Hu, Tianxing Ma, Hai-Qing Lin, Bing Huang