Ta2NiSe5 nanosheets as a novel broadband saturable absorber for solid-state pulse laser generation

Abstract

Two-dimensional (2D) ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect and stoichiometric variation with the additional third element compared with their binary counterparts. Here, high-quality 2D tantalum nickel selenide (Ta 2 NiSe 5 ) nanosheets are successfully fabricated by a liquid-phase exfoliation (LPE) method. The ultrafast excited carrier relaxation time and nonlinear optical absorption response are investigated and reveal that the prepared 2D Ta 2 NiSe 5 nanosheets have excellent broadband saturable absorption properties, which are further illustrated by three passively Q-switched (PQS) all-solid-state lasers operating at 1.0, 2.0 and 2.8 µm with the Ta 2 NiSe 5 nanosheet-based saturable absorber (SA). Furthermore, mode-locked laser operation with the pulse width as short as 356 fs is also realized at 1.0 µm. This work not only demonstrates the excellent nonlinear optical proprieties and optical modulation performance of Ta 2 NiSe 5 , but also paves the way for exploring the photonic and optoelectronic proprieties of ternary chalcogenide materials. 三元硫族化合物与其二元的同类相比, 因其多出的第三种元素而产生的协同作用和化学计量变化带来了新奇的物理化学性质, 从而受到了广泛的关注. 在本文中, 我们通过液相剥离法成功制备了高质量的二维硒化镍钽(Ta 2 NiSe 5 )纳米片, 并进一步研究了其超快载流子弛豫特性以及非线性光学吸收特性, 从而发现了所制备的Ta 2 NiSe 5 纳米片具有出色的宽带可饱和吸收性能. 此外, 利用所制备的Ta 2 NiSe 5 纳米片作为可饱和吸收体, 实现了在1.0, 2.0和2.8 µm处的全固态调Q脉冲激光. 同时, 在1.0 µm处也实现了脉冲宽度短至356 fs 的固体连续锁模激光. 这项工作不仅证明了Ta 2 NiSe 5 具有优异的非线性光学特性和光调制性能, 而且为探索三元硫族化物材料的光子和光电特性铺平了道路.