Miniaturized broadband highly birefringent device with stereo rod-microfiber-air structure

A wrapping-on-a-rod technique is presented and demonstrated successfully to realize broadband microfiber-based highly birefringent (Hi-Bi) devices with 3D geometry. By wrapping a circular microfiber (MF) on a Teflon-coated rod (2 mm in diameter), a large and broadband birefringence can be obtained utilizing a rod-microfiber-air (RMA) structure. Wavelength scanning method is used to measure the birefringence of the device. Results show that group birefringence as high as 10(-3) can be achieved over 400 nm wavelength range. This compact element presents great potential in sensing and communication applications, as well as lab-on-a-rod devices.