The Dielectric Properties of Hfs3 And its Application in Ultrafast Laser

Abstract

As a member of the transition metal chalcogenides family, hafnium trisulfid (HfS3) has gained considerable interest in the realm of optoelectronics due to the distinctive optical and electronic properties. Notwithstanding this interest, there remains a paucity of comprehensive investigations into the saturable absorption characteristics and ultrafast laser applications of HfS3. In this study, we employed a liquid exfoliation methodology to synthesize HfS3 nanosheets, which were subsequently utilized to prepare a HfS3-microfiber saturable absorber (SA). The SA exhibited a nonsaturable loss (αns) of 33.13% and a modulation depth (αs) of 10.72%. The dielectric properties of HfS3 were studied theoretically. We integrated the fabricated HfS3-microfiber into an Er-doped fiber (EDF) laser cavity in order to clarify the possible use of HfS3 as a saturable absorber. Our findings demonstrate that the HfS3-based SA produced mode-locked laser pulses with a narrow pulse duration of 492 fs and the signal-to-noise ratio (SNR) of 85 dB. Moreover, the fiber laser can operate in a Q-switching state with repetition frequency from 39.157 kHz to 113.93 kHz. Our work demonstrated that HfS3 nanosheets have outstanding nonlinear properties and play an extremely important role in the field of ultrafast photonics.

Keywords: nonlinear optics, hafnium trisulfid, mode-locked, ultrafast pulse, high signal-to-noise ratio