von Milczewski Jonas, Chen Xin, Imamoglu Atac, Schmidt Richard
Institute for Theoretical Physics, Heidelberg University, Philosophenweg 16, 69120 Heidelberg, Germany.
<a href="https://ror.org/01vekys64">Max-Planck-Institute of Quantum Optics</a>, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany.
Phys Rev Lett. 2024 Nov 29;133(22):226903. doi: 10.1103/PhysRevLett.133.226903.
We study a mechanism to induce superconductivity in atomically thin semiconductors where excitons mediate an effective attraction between electrons. Our model includes interaction effects beyond the paradigm of phonon-mediated superconductivity and connects to the well-established limits of Bose and Fermi polarons. By accounting for the strong-coupling physics of trions, we find that the effective electron-exciton interaction develops a strong frequency and momentum dependence accompanied by the system undergoing an emerging BCS-BEC crossover from weakly bound s-wave Cooper pairs to a superfluid of bipolarons. Even at strong-coupling the bipolarons remain relatively light, resulting in critical temperatures of up to 10% of the Fermi temperature. This renders heterostructures of two-dimensional materials a promising candidate to realize superconductivity at high critical temperatures set by electron doping and trion binding energies.
我们研究了一种在原子级薄半导体中诱导超导性的机制，其中激子介导电子之间的有效吸引。我们的模型包括声子介导超导范式之外的相互作用效应，并与玻色极化子和费米极化子的成熟极限相关联。通过考虑三重子的强耦合物理，我们发现有效的电子 - 激子相互作用呈现出强烈的频率和动量依赖性，同时系统经历从弱束缚s波库珀对到双极化子超流体的新兴BCS - BEC转变。即使在强耦合下，双极化子仍然相对较轻，导致临界温度高达费米温度的10%。这使得二维材料的异质结构成为在由电子掺杂和三重子结合能设定的高临界温度下实现超导性的有前途的候选者。
