Bulk Nb superconducting radio-frequency (SRF) cavities are widely used in accelerators, and their accelerating gradient and general performance are limited by the superheating field (B _sh). To push the theoretical limit of the B _sh, new multilayer structures are required. We fabricated FeSe-coated Nb films using pulsed laser deposition, performed structural characterizations, and measured the transport and magnetic properties for this superconductor-superconductor bilayer structure with smooth surface. Additionally, the measured B _c1 of FeSe-coated Nb film is greatly enhanced, while the B _sh of the FeSe layer is expected to be higher than that of bulk Nb, yet the superconducting transition temperature (T _c) is less than 5 K. This work presents the first fabrication of a new coating layer: FeSe deposited on Nb, showing the possibility of using iron-based materials for multilayer structures in SRF cavities.

块状Nb超导射频（SRF）腔已广泛用于加速器中，其加速梯度和总体性能受到过热场（B _sh）的限制。为了突破B _sh的理论极限，需要新的多层结构。我们使用脉冲激光沉积技术制备了FeSe涂层的Nb薄膜，进行了结构表征，并测量了具有光滑表面的超导体-超导体双层结构的输运和磁性。此外，FeSe涂层的Nb薄膜的测得的B _c1大大提高，而B _shFeSe层的Nb有望高于块状Nb，但超导转变温度（T _c）小于5K。这项工作提出了一种新涂层的首次制造方法：FeSe沉积在Nb上，表明了可能性SRF腔体中的多层结构使用铁基材料的研究。