Orbital angular momentum (OAM) multiplexing technology is expected as one of the prospective candidates for sustaining further increment data-transmission capacity in optical communication systems. Advanced combining OAM-based mode division (MDM) multicore fiber (MCF) with wavelength (WDM) can improve transmission rate and spectrum efficiency In this paper, a multi-ring-air-core (MRACF) supporting thousands OAM modes designed analyzed. The tradeoffs between ring number/density their...

Abstract To meet the ever-increasing demand for data rate and bandwidth, mode-division-multiplexing technology utilizing orbital angular momentum (OAM) emerges as a promising solution to substantially expand transmission capacity of optical fiber communication systems. In this work, we propose numerically investigate refractive index profile multi-core fiber, termed seven-core trench-assisted-graded-index ring fiber. This designed introduces graded-index enhance OAM mode purity increase...

We design a graded-index ring-core fiber with GeO2-doped silica ring core and SiO2 cladding. This structure can inhibit the effect of spin-orbit coupling to mitigate power transfer among different modes eventually enhance orbital angular momentum (OAM) mode purity. By changing high-index from step-index parabolic profile, purity OAM1,1 be improved 86.48% 94.43%, up by 7.95%. The proposed features flexible structure, which meet requirements for order, effective area, etc. Simulation results...

In this paper, we propose and design a multi-orbital-angular-momentum multi-ring air-core fiber, which has seven high-index rings with each ring supporting 62 radially fundamental OAM modes across C L bands (from 1530 nm to 1625 nm), i.e. 434 in total. The designed fiber features >4×10 −4 intra-ring modal indices difference for the same topological charge l bands. Moreover, it can keep <−52 dB crosstalk between adjacent at 1550 nm, <−24 after 100-km propagation. This kind of...

Orbital angular momentum (OAM) modes have becoming more promising to further achieve higher spectral efficiency and data capacity in space-division-multiplexing (SDM) fiber communication systems. In this work, we design optimize a graded-index non-zero dispersion-shifted ring-core (GI-NZDSRF) support OAM fiber-based transmission system. A record high number of 60 the C band with <10 ps/nm/km chromatic dispersion (CD) is obtained. low differential mode delay (DMD) (<5.11 ps/m) large effective...

Due to the unique features, orbital angular momentum (OAM) beams have been widely explored for different applications. Accurate determination of topological charge (TC) these is crucial their optimal utilization. In this paper, we propose a method that combines adaptive image processing techniques with simple, parameter-free attention module (SimAM) based convolutional neural network accurately identify TC high-order superimposed OAM beams. Experimental results demonstrate under combined...

As the dimension of orbital angular momentum (OAM) is orthogonal to other degrees freedom for photon, such as wavelength, it can be utilized further increase data capacity in wavelength division multiplexing (WDM) systems. However, non-zero dispersion-shifted fiber (NZDSF) OAM mode has not yet been investigated or even proposed. In this work, we propose and design a ring with low chromatic dispersion HE 2,1 mode, which serve NZDSF its corresponding 1,1 mode. A 3.3 ps/(nm·km) at 1550 nm...

We propose and design a 19-ring-air-core fiber that can support about 3000 orbital angular momentum (OAM) modes (156 in each ring) with <-80 dB inter-ring cross talk across the entire C L bands after 100-km propagation. Moreover, eigenmodes are all separated from their adjacent by effective index differences >2.67 × 10-4 mode groups > 1.90 10-2, which guarantee stable transmission of OAM modes. This designed is potential candidate for applications spatial division multiplexing (SDM) optical...

A well designed ring-core fiber can theoretically support numerous orbital angular momentum (OAM) modes with low crosstalk for space-division-multiplexing (SDM) data transmission, which is considered as a promising solution overcoming the capacity crunch in optical communication network. However, accumulated chromatic dispersion OAM-fiber could limit speed and transmission distance of systems. potential to insert compensation opposite-sign along link. In this work, we propose triple...

In this paper, we design a silica-cladded Germania-doped ring-core fiber (RCF) that supports orbital angular momentum (OAM) modes. By optimizing the structure parameters, RCF possesses near-zero flat dispersion with total variation of <±30 ps/nm/km over 1770 nm bandwidth from 1040 to 2810 for OAM1,1 mode. A beyond-two-octave supercontinuum spectrum mode is generated numerically by launching 40 fs 120 kW pulse train centered at 1400 into 12 cm long designed 50 mol% Ge-doped fiber, which...

Orbital angular momentum (OAM) multiplexing technology has attracted significant interest due to its ability increase the data transmission capacity in optical communications. By combining OAM-based mode division (MDM) and wavelength (WDM) techniques multi-core fiber (MCF), rate spectral efficiency of communication systems can be greatly enhanced. In this paper, we present a design multi-ring air-core trench-assisted that supports over entire C + L (1530–1625 nm) band with low inter-ring...

It is well-known now that orbital angular momentum (OAM) modes can be a potential technology to take full advantages of the space resources in fiber-based optical communication system because its infinite states. However, corresponding fiber design for OAM meet various requirements still not enough. For dispersion property, there are attributes given standard ITU-T series, which has yet been proposed modes. In this paper, we propose and non-zero dispersion-shifted air-core ring mode, offer...

In this paper, we propose and design a Ge-doped air-core ring fiber, which can support large amount of OAM modes for mode-division multiplexing (MDM) in optical fiber communications. By varying the mole fraction GeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> adjusting structure parameter, including radius -doped width, investigate influence different parameters on total supported mode number. The hollow silica with 50- μm air core...

In this work, we design and numerically investigate a silica-cladded Germania-doped ring-core fiber (RCF) that supports orbital angular momentum (OAM) modes with all-normal dispersion. By optimizing the structure parameters of designed RCF, an flat dispersion total variation < 60 ps/nm/km over 1035-nm bandwidth from 965 to 2000 nm is realized for OAM1,1 mode. A 1.3-octave supercontinuum spectrum mode generated after launching 40-fs 200-kW chirp-free hyperbolic secant pulse train centered at...

We propose and design non-zero dispersion-shifted ring fiber for OAM Mode. A low dispersion of 3.3 ps/(nm·km) at 1550 nm &lt;2.9 variation from 1530 to 1565 OAM1,1 mode is achieved.

Several types of ring-core optical fibers are presented for OAM modes, including multi fiber supporting thousands coupled with large dispersion, and non-zero dispersion-shifted to balance dispersion nonlinearity.

A trench-assisted seven-core non-zero dispersion shifted ring fiber is designed to support 98 OAM modes, which can maintain &lt;-40 dB crosstalk across the C-band. Large effective mode area and low differential delay are also achieved.

A multi-concentric-ring-core non-zero dispersion shifted fiber is proposed and designed to support 70 OAM modes while adhering the ITU-T G.655.C standard. The corresponding nonlinear effects confinement loss of are investigated.

Trench-assisted seven-core graded-index ring fiber is proposed and designed to support 210 OAM modes in the C-band with &gt; 99.27% purity. It features &lt; -90 dB crosstalk for majority of supported modes.

OAM mode purity in graded-index ring-core fiber with different shape factors is investigated. The of 1,1 significantly increased from 86.48% to 94.43% by changing the step-index parabolic profile.