Pulse-Width Tuning in a Passively Mode-Locked Fiber Laser With Graphene Saturable Absorber

Abstract

An absorption-adjustable graphene saturable absorber is used in a simple fiber laser system for an active control of the pulse-width of optical pulses. Such a saturable absorber is created by tightly attaching the graphene film onto the upper surface of the microfiber, thus an enhanced evanescence-field interaction between the propagating light along the microfiber length and graphene can be achieved. By tuning the polarization state of the light beam launched into the saturable absorber from TE to TM mode, the pulse-width of the pulses is varied between ∼9.24 and ∼2.32 ps.

2D Layered Materials: Synthesis, Nonlinear Optical Properties, and Device Applications

“…With this scheme, a large number of high repetition-rate lasers based on layered materials have been developed. [179,180,207,208,216,232,238,241,243,260,278,298] Among them, the maximum repetition rate is 106.7 GHz. [232] These works paved the way for the practical application of high repetition-rate mode-locked lasers.…”

“…In addition, compared with traditional SAs, including semiconductor saturable absorber mirrors or carbon nanotubes, graphene does not require bandgap optimization and diameter or chiral adjustment, thus greatly simplifying the preparation process. With these advantages, graphene and its derivatives, such as graphene oxide, reduced graphene oxide, and graphene composite materials, have been widely developed in mode‐locked fiber lasers, as shown in Table . In terms of the performance of these mode‐locked lasers, some exciting results have been obtained, including minimum pulse‐width, maximum output power, and repetition rates of 29 fs, 520 mW, and 162 GHz, respectively.…”

Recent progress on applications of 2D material-decorated microfiber photonic devices in pulse shaping and all-optical signal processing

“…The higher optical damage threshold of such photonic devices greatly motivated the research of 2D material-decorated microfiber SAs. After that, the graphene-decorated microfiber was used to achieve the operation of multiwavelength [174], wavelength-tunable [165,176], and pulse durationtunable [167][168][169]176] in Er-doped mode-locked fiber lasers. Apart from graphene, many other 2D materials, such as TIs, TMDs, BP, and gold nanorod, possess the characteristic of saturable absorption, indicating that they can be deposited onto the microfiber as SAs for ultrafast photonics applications.…”

Electrically Controllable Saturable Absorption in Hybrid Graphene-Silicon Waveguides

“…The voltage dependence of the nonlinear absorption of the structure is investigated and tunable saturable absorption is demonstrated. Since the saturable absorption modulation depth can strongly influence the pulse duration of mode-locked lasers [6], the concepts demonstrated in this work could eventually lead to integrated spontaneously mode-locked lasers with an electrically tunable pulse duration. …”