Intermodal interference of LP0j modes in optical fiber with liquid core

We present intermodal interference of modes LP0j in silica optical fiber with liquid core. An appropriate detection method is proposed for observation of intermodal interference of LP0j modes. Measured spectral dependencies reveal a clear local minimum, where position is a function of optical fiber parameters. We focused on investigation of dependence of that minimum position on length of optical fiber with liquid core. From measured spectral dependencies the evident blue shift of local minimum is observed as length of optical fiber increases. Character of spectral characteristics correspond with intermodal interference of modes LP0j and is demonstrated by numerical calculations. Presented intermodal interference in combination with liquid-filled core of optical fiber can be attractive for sensing applications.