Transition metal-doped Sb₂Se₃ has become a heated topic caused by the strong nonlinear optical response and the ultrafast response time at high laser excitation. In this paper, the Co-doped Sb₂Se₃ with different doping amount (0.5, 1.0, and 1.5 W) nanofilms were prepared by magnetron sputtering technology, and the nonlinear behavior of Co-doped Sb₂Se₃ nanofilms at near infrared were systematically studied. The results of the femtosecond Z-Scan experiment indicate that the Co-doped Sb₂Se₃ nanofilms exhibit broadband nonlinear response properties owing to the free carrier absorption, the Kerr refraction, the two-photon absorption, and the free carrier refraction. The nonlinear absorption coefficients of Co-doped Sb₂Se₃ nanofilms are from 3.0 × 10⁻⁹ to 2.03 × 10⁻⁸ m/ W under excitation at 800, 980, and 1,030 nm, and the nonlinear refractive index of the Co-doped Sb₂Se₃ nanofilms is from 4.0 × 10⁻¹⁶ to -3.89 × 10⁻¹⁵ m²/ W at 800, 980, and 1,030 nm. More importantly, Co-doped Sb₂Se₃ (1.5 W) nanofilm exhibits ultrafast carrier absorption (<1 ps) and a stronger transient absorption intensity of ΔOD > 6.3. The Co-doping content can controllably tune the crystalline degree, the ultrafast carrier absorption, the intensity of the reverse saturation absorption, the broadband nonlinear optical response, and the carrier relaxation time of Co-doped Sb₂Se₃ nanofilms. These results are sufficient to support their applications in broadband nonlinear photonic devices.

由于强非线性光学响应和高激光激发下的超快响应时间，过渡金属掺杂的 Sb ₂ Se ₃已成为热门话题。在本文中，所述共掺杂的Sb ₂硒₃采用磁控溅射技术制备的具有不同掺杂量（0.5，1.0和1.5 W）纳米膜，和的非线性行为共掺杂Sb的₂硒_3个在近红外纳米膜是系统地研究过。飞秒Z-Scan实验结果表明Co掺杂Sb ₂ Se ₃由于自由载流子吸收、克尔折射、双光子吸收和自由载流子折射，纳米薄膜表现出宽带非线性响应特性。Co掺杂Sb ₂ Se ₃纳米薄膜在800、980 和1,030 nm激发下的非线性吸收系数为3.0 × 10 ^-9至2.03 × 10 ^-8 m/W，Co掺杂的非线性折射率Sb ₂ Se ₃纳米膜在800、980和1,030nm处为4.0×10 ^-16至-3.89×10 ^-15  m ² / W。更重要的是，Co掺杂的Sb ₂ Se ₃(1.5 W) 纳米膜表现出超快的载流子吸收 (<1 ps) 和更强的瞬态吸收强度 ΔOD > 6.3。Co掺杂含量可以可控地调节Co掺杂Sb ₂ Se ₃纳米薄膜的结晶度、超快载流子吸收、反向饱和吸收强度、宽带非线性光学响应和载流子弛豫时间。这些结果足以支持它们在宽带非线性光子器件中的应用。