Design and optimization of photonic crystal fiber with low confinement loss guiding 98 OAM modes in THz band

•A novel THz ring core PCF is proposed. The PCF supports 98 stable modes in the THz band (1THz–3THz).•Versatile design with low dispersion (∼0.02 ps/THz/cm), low confinement loss (∼10−11 dB/m) and high mode purity (>0.86).•Material absorption and fiber bending loss (bending radius 2 cm–10 cm) is studied.•PCF features low intermodal crosstalk along with high bending tolerance.