In recent years, multigap superconductors have attracted much attention since the discovery of novel two-gap superconductivity with transition temperature $T_c\sim 39\text{K}$ in bulk ${\mathrm{MgB}}_2$. Based on the first-principles calculation and anisotropic Migdal-Eliashberg theory, we conduct a study on a series of two-dimensional (2D) boron-based materials with doped metal atoms to search for multigap superconductors. We find that ${\mathrm{InB}}_2$ monolayer films and ${\mathrm{InB}}_4$ trilayer films are dynamically stable but not synthesized experimentally yet. An evident three-gap superconductor with high $T_c\sim$ 41.5 K is obtained in a ${\mathrm{InB}}_2$ monolayer film. Similarly, ${\mathrm{InB}}_4$ trilayer film is a novel superconductor with three distinct superconducting gaps and a high $T_c\sim$ 53 K. The superconductivity in both 2D films originates mainly from the covalent-state-driven metallization. In addition, the effect of biaxial strain on the superconducting behavior of $\mathrm{In}{\text{B}}_4$ trilayer films is also involved. The ${\mathrm{InB}}_4$ trilayer films stay dynamically stable under biaxial tensile strain of $-3\%–6\%$, and the highest $T_c$ boosts to 64 K under the biaxial tensile strain of $\sim 4\%$. Meanwhile, we also find that the ${\mathrm{GeB}}_4$ and ${\mathrm{ZnB}}_4$ trilayer films are two-gap superconductors with high $T_c\sim$ 48.5 and 32 K, respectively.

中文翻译：

---

二维InB2/InB4薄膜中的三能隙超导性

近年来，自发现具有转变温度的新型两带隙超导性以来，多带隙超导体备受关注。 ${吨}_C～39\text{钾}$ 散装 ${\mathrm{镁硼}}_2$. 基于第一性原理计算和各向异性 Migdal-Eliashberg 理论，我们对一系列具有掺杂金属原子的二维 (2D) 硼基材料进行了研究，以寻找多隙超导体。我们发现${\mathrm{英博}}_2$ 单层薄膜和 ${\mathrm{英博}}_4$三层薄膜是动态稳定的，但尚未通过实验合成。一种明显的三能隙超导体，具有高${吨}_C～$ 41.5 K 是在一个 ${\mathrm{英博}}_2$单层薄膜。相似地，${\mathrm{英博}}_4$ 三层薄膜是一种新型超导体，具有三个不同的超导间隙和高 ${吨}_C～$53 K. 两种 2D 薄膜中的超导性主要来自共价态驱动的金属化。此外，双轴应变对超导行为的影响$在{\text{乙}}_4$也涉及三层膜。这${\mathrm{英博}}_4$ 三层薄膜在双轴拉伸应变下保持动态稳定 $-3\%——6\%$，并且最高 ${吨}_C$ 在双轴拉伸应变下升至 64 K $～4\%$. 同时，我们还发现，${锗}_4$ 和 ${\mathrm{锌硼}}_4$ 三层薄膜是两间隙超导体，具有高 ${吨}_C～$ 分别为 48.5 和 32 K。