Group-Birefringence-Dispersion Measurements for Polarization-Maintaining Fibers Using a Kerr Phase-Interrogator

Yang Lu

doi:10.3390/app10249031

Abstract

A method which utilizes a Kerr phase-interrogator to measure the group birefringence dispersion (GBD) of a polarization-maintaining fiber (PMF) is systematically studied in this paper. The differential group delay of two sinusoidally modulated optical signals (SMOSs) polarized along the principal axes of the PMF is measured by a Kerr phase-interrogator, which leads to the group birefringence of the PMF. As the laser wavelength of the SMOSs varies, the group birefringence as a function of the laser wavelength is obtained, and the GBD is calculated as the derivative of the group birefringence with respect to the laser wavelength. The proposed method is experimentally demonstrated by characterizations of a Panda PMF with high GBD and an elliptical core PMF with low GBD, and its performance is analyzed. The proposed method eliminates the impact of the laser coherent length and allows for characterizing the GBD of PMFs that are tens of kilometers long.

Highlights

Polarization-maintaining fibers (PMFs) with lengths of hundreds of meters have been applied in many fields, such as ultrafast all-optical switching and ultrashort pulse generation [1,2]
The group birefringence dispersion (GBD) of a PMF governs the temporal profiles of amplitudes and spectra of optical pulses through nonlinear optical effects
The electro-optic modulator (EOM) is driven by a sinusoidal electrical signal oscillating at radio frequency fm and turns the continuous light-wave (CW) into an sinusoidally modulated optical signals (SMOSs) oscillating at a radio frequency fs = 2 fm

Summary

Introduction

Polarization-maintaining fibers (PMFs) with lengths of hundreds of meters have been applied in many fields, such as ultrafast all-optical switching and ultrashort pulse generation [1,2]. In these applications, the group birefringence dispersion (GBD) of a PMF governs the temporal profiles of amplitudes and spectra of optical pulses through nonlinear optical effects. PMFs have been employed in distributed stress sensors [3]. Because of the GBD of the PMF, the spatial resolution of stress measurements deteriorates with fiber distance. Characterization of the GBD of the long PMF mitigates the impact of birefringence dispersion on distributed stress measurements

Methods

Results

Discussion

Conclusion