  We introduce a simple approach to fabricate aligned carbon nanotube (ACNT)
device for broadband polarization control in fiber laser systems. The ACNT
device was fabricated by pulling from as-fabricated vertically-aligned carbon
nanotube arrays. Their anisotropic property is confirmed with optical and
scanning electron microscopy, and with polarized Raman and absorption
spectroscopy. The device was then integrated into fiber laser systems (at two
technologically important wavelengths of 1 and 1.5 um) for polarization
control. We obtained a linearly-polarized light output with the maximum
extinction ratio of ~12 dB. The output polarization direction could be fully
controlled by the ACNT alignment direction in both lasers. To the best of our
knowledge, this is the first time that ACNT device is applied to polarization
control in laser systems. Our results exhibit that the ACNT device is a simple,
low-cost, and broadband polarizer to control laser polarization dynamics, for
various photonic applications (such as material processing, polarization
diversity detection in communications), where the linear polarization control
is necessary.
