RESUMEN
Understanding the impact of the cladding tube structure on the overall guiding performance is crucial for designing a single-mode, wide-band, and ultra low-loss nested hollow-core anti-resonant fiber (HC-ARF). Here we thoroughly investigate on how the propagation loss is affected by the nested elements when their geometry is realistic (i.e., non-ideal). Interestingly, it was found that the size, rather than the shape, of the nested elements has a dominant role in the final loss performance of the regular nested HC-ARFs. We identify a unique 'V-shape' pattern for suppression of higher-order modes loss by optimizing free design parameters of the HC-ARF. We find that a 5-tube nested HC-ARF has wider transmission window and better single-mode operation than a 6-tube HC-ARF. We show that the propagation loss can be significantly improved by using anisotropic nested anti-resonant tubes elongated in the radial direction. Our simulations indicate that with this novel fiber design, a propagation loss as low as 0.11 dB/km at 1.55 µm can be achieved. Our results provide design insight toward fully exploiting a single-mode, wide-band, and ultra low-loss HC-ARF. In addition, the extraordinary optical properties of the proposed fiber can be beneficial for several applications such as future optical communication system, high energy light transport, extreme non-nonlinear optics and beyond.
RESUMEN
We show that adiabatic down-conversion can be made the dominant four-wave mixing process in an anti-resonant hollow-core fiber for nearly a full octave of mid-infrared bandwidth with energy exceeding 10 µJ, allowing the generation of energetic and shapeable two-cycle pulses. A numerical study of a tapered fiber with an applied gas pressure gradient predicts the efficient conversion of a 770-860 nm near-infrared frequency band to 3-5 µm, while a linear transfer function allows pre-conversion pulse shaping and simple dispersion management. Our proposed system may prove to be useful in diverse research topics employing nonlinear spectroscopy or strong light-matter interactions.
RESUMEN
We investigate numerically soliton-plasma interaction in a noble-gas-filled silica hollow-core anti-resonant fiber pumped in the mid-IR at 3.0 µm. We observe multiple soliton self-compression stages due to distinct stages where either the self-focusing or the self-defocusing nonlinearity dominates. Specifically, the parameters may be tuned so the competing plasma self-defocusing nonlinearity only dominates over the Kerr self-focusing nonlinearity around the soliton self-compression stage, where the increasing peak intensity on the leading pulse edge initiates a competing self-defocusing plasma nonlinearity acting nonlocally on the trailing edge, effectively preventing soliton formation there. As the plasma switches off after the self-compression stage, self-focusing dominates again, initiating another soliton self-compression stage in the trailing edge. This process is accompanied by supercontinuum generation spanning 1-4 µm. We find that the spectral coherence drops as the secondary compression stage is initiated.
RESUMEN
This publisher's note corrects Eq. (1) of Opt. Lett.42, 2232 (2017)OPLEDP0146-959210.1364/OL.42.002232.
RESUMEN
We present a new cladding design for photonic crystal fiber (PCF) on a decagonal structure to simultaneously achieve ultra-flattened large negative dispersion and ultrahigh birefringence. Numerical results confirm that the proposed PCF exhibits ultra-flattened large negative dispersion over the S+C+L+U wavelength bands and average dispersion of about -558.96 ps/nm/km with absolute dispersion variation of 9.7 ps/nm/km from 1460 to 1675 nm (215 nm bandwidth). Moreover, ultrahigh birefringence of 0.0299 is also achieved at a 1500 nm wavelength.