Graphene Self-Phase-Lockers Formed around a Cu Wire Hub for Ring Resonators Incorporated into 57.8 Gigahertz Fiber Pulsed Lasers

Abstract

We demonstrate graphene-functionalized self-phase-locking of laser pulses for a dramatically elevated repetition rate by employing an intrinsic resonating structure in a fiber ring laser cavity, the modes thereby satisfying the phase-matching condition passively, through both the resonator and the laser cavity. Graphene is directly synthesized around a 1-mm-diameter Cu wire catalyst, avoiding the deleterious transfer process. The wire provides a form factor to the fiber ring resonator as a versatile winding hub, guaranteeing damage-minimized and recyclable contact of the synthesized graphene with a diameter-controlled optical microfiber. In-depth analysis of the graphene confirms the optical nonlinearity critically required for pulse formation. The laser–graphene interaction, the intermode phase-locking function of graphene, and the pulse formation with the resonator are systematically elucidated to explain the experimentally generated laser pulses at a repetition rate of 57.8 gigahertz (GHz). Additionally, tunability of the repetition rate up to 1.5 GHz by the photothermal effect of graphene is demonstrated.

Ultrafast Fiber Lasers with Low-Dimensional Saturable Absorbers: Status and Prospects

“…Therefore, it is obvious that exploring novel 2D materials as SA is continuous since it was first implemented. In addition, the controllability of key features in current 2D SAs and engineering in the laser cavity with tunable behavior of SAs also offers more functionalities in the development of controllable ultrafast fiber lasers [ 25 , 26 , 27 , 66 , 68 , 101 ]. Combining two or more similar or different 2D materials and building van der Waals heterostructures prospects towards developing multi-functional, high efficiency, broadband controllable photonic devices [ 102 , 103 ].…”

“…Nevertheless, this method undergoes deleterious transfer steps from the grown substrate to the fiber system to build the SA device, making this technique complicated to realize cost-effective devices [ 21 , 116 , 117 ]. To solve these issues, direct synthesis methods have been reported for graphene to build nonlinear optical devices including SA devices [ 32 , 101 , 118 , 119 , 120 ].…”

Temperature‐ and Ambient Pressure‐Independent Sensing of Hydrogen in Fluids Using Cascaded Interferometers Incorporated in Optical Fibers

“…[33][34][35][36] In particular, optical devices incorporated in a fiber-optic system can provide long-distance remote control enabled by ultra-low propagation loss of the fiber, reliable operation based on the stable optical fiber structure, high flexibility, and multiplexed monitoring of sensors employing only a single broadband light source. [38][39][40][41][42] Recently, an optical hydrogen sensor with a Fabry-Perot interferometer (FPI) formed using an atomically thin membrane at the end of an optical fiber was proposed and demonstrated with a low detection limit, a short response time, and a high hydrogen sensitivity. [43] However, its practical application was limited by temperature-and pressuredependent sensing, along with its fragile structure.…”

Directly Synthesized Graphene-Based Photonics and Optoelectronics Devices

“…Nevertheless, graphene is an ideal photonic and optoelectronic material due to the broadband optical properties [8][9][10][11][12][13][14]. The aforementioned characteristics forge the path for graphene to be a potential material for optoelectronic and photonic applications [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30].…”