Solid-core anti-resonant fiber based on silicate glass

In this paper, we report the design, fabrication, and characterization of a passive silicate-glass-based all-solid anti-resonant fiber (AS-ARF) for ∼1 µm transmission suppression. Simulation results demonstrate that the AS-ARF achieves a first high higher order mode (HOM) suppression ratio of over 25 dB in a 26-63 µm core diameter at 1550 nm. Using the drilling and rod-in-tube technique, an AS-ARF was fabricated with a core diameter of 43 µm, a core NA of 0.023, and high-refractive-index capillaries (HRICs) thickness of 1.4 µm. Furthermore, a wide transmission window around 1.5 µm, and a high-loss resonant band ranging from 1 µm to 1.1 µm were measured, which agrees well with the simulation. By fusion spliced a 12 cm-long AS-ARF in the EYDF amplifier, amplified spontaneous emission (ASE) and parasitic oscillations of Yb3+ ions are effectively suppressed, and the loss at 1030 nm is 12.3 dB higher than that at 1550 nm. To the best of our knowledge, this is the first time that an AS-ARF can achieve ∼1 µm transmission suppression and single-mode propagation in the 1.5 µm band. The fiber structure option holds potential for further application in rare-earth-doped fiber amplifiers and lasers, including those doped with Nd, Yb, Er, Tm, and other rare-earth elements.

Design and fabrication of all-solid anti-resonant silicate fibers for Yb ASE suppression in Er/Yb fiber amplifier

Cheng,

Yang,

Zhu

et al. 2024

Large-mode-area Nd-doped anti-resonant phosphate fiber for high-power single-mode 900 nm laser generation

Fu,

Xu,

Tian

et al. 2024

In this work, we propose an Nd-doped double-layer anti-resonant phosphate fiber with a core diameter of 50 µm for high-power single-mode 900 nm laser generation. Double-layer interlaced anti-resonant elements were designed here to enhance the fundamental mode confinement capability of the large-mode-area Nd-doped fiber core. Moreover, a double-layer F-P etalon formed between the anti-resonant elements and the inner cladding was analyzed for the first time for fiber loss manipulation. Single-mode operation in the 890–907 nm band with confinement loss lower than 0.1 dB/m can be achieved from the designed fiber. More importantly, high confinement loss larger than 100 dB/m is achieved for all the fiber modes around 1060 nm for four-level gain competition suppression in 900 nm Nd-doped fiber laser generation. A 900 nm fiber amplifier simulation based on the designed Nd-doped phosphate fiber shows that the parasitic lasing or even amplified spontaneous emission around 1060 nm can be effectively suppressed and a high-efficiency hundred-watt laser at 900 nm can be anticipated.

Ultra-large mode field area single-mode all-solid anti-resonant fiber with open arc elements in the cladding

Gao,

Wang,

Ding

et al. 2024

What we believe to be a novel ultra-large mode field area (MFA) single-mode all-solid anti-resonant fiber (ARF) is proposed. Different from the large mode area (LMA) all-solid ARF with double layers of rods in the cladding, the proposed fiber utilizes open arc elements in the second layer instead of circular rods to simultaneously achieve the ultra-large MFA and high single-mode performance. Especially, the outer diameter (OD) of the fiber can be efficiently decreased in comparison with other LMA fibers with the same MFA. Through the combination of enlarging core diameter and adjusting the distance of the two layers of anti-resonant elements to expand the MFA, an ultra-large MFA of 15647 µm2 can be achieved at the wavelength of 1.064 µm, which is 2 times that of the largest MFA of the previously reported all-solid ARF. The ratio of the lowest loss of higher-order modes to the loss of the fundamental mode can reach up to 23797 and thus high single-mode performance can be simultaneously implemented. Moreover, the OD of the designed fiber is only 578 µm, which is almost a quarter of that of the previous rod-type photonic crystal fiber and the mainstream large-pitch fiber (approximately 1.5-2 mm). To the best of our knowledge, it is the smallest OD among the currently reported ultra-LMA fibers with an MFA greater than 10000 µm2. In addition, the tolerance to the change of fiber parameters is also discussed, demonstrating that the proposed fiber has a wide parameter tolerance range. Numerical results show that the all-solid ARF will be a great candidate for the future development of ultra-large MFA fiber.