Interband Short Reach Data Transmission in Ultrawide Bandwidth Hollow Core Fiber

We report a Nested Antiresonant Nodeless hollow-core Fiber (NANF) operating in the first antiresonant passband. The fiber has an ultrawide operational bandwidth of 700 nm, spanning the 1240-1940 nm wavelength range that includes the O-, S-, C- and L- telecoms bands. It has a minimum loss of 6.6 dB/km at 1550 nm, a loss ≤7 dB/km between 1465-1655 nm and ≤10 dB/km between 1297-1860 nm. By splicing together two structurally matched fibers and by adding single mode fiber (SMF) pigtails at both ends we have produced a ~1 km long span. The concatenated and connectorized fiber has an insertion loss of approximately 10 dB all the way from 1300 nm to 1550 nm, and an effectively single mode behavior across the whole spectral range. To test its data transmission performance, we demonstrate 50-Gb/s OOK data transmission across the O-to L-bands without the need for optical amplification, with bit-error-rates (BERs) lower than the 7% forward error correction (FEC) limit. With the help of optical amplification, 100-Gb/s PAM4 transmission with BER lower than the KP4 FEC limit was also achieved in the O/E and C/L bands, with relatively uniform performance for all wavelengths. Our results confirm the excellent modal purity of the fabricated fiber across a broad spectral range, and highlight its potential for wideband, low nonlinearity, low latency data transmission.