Design for controllable optofluidic beam splitter

•A novel reconfiguration for tunable optofluidic beam splitter is firstly proposed by us.•The tunable optofluidic beam splitter exhibits excellent optical performance.•It has large fabrication tolerance, weak dependence on wavelength and polarization.

A novel configuration for controllable optofluidic beam splitter is proposed, which consists of the asymmetric Y-branch waveguide and the microfluidic channel filled with fluid mixture. The beam propagation method (BPM) is employed to numerically investigate the optical performance of device in our layout. The simulated results demonstrate that arbitrary splitting ratio and low optical loss for both TE and TM mode can be easily achieved, with a low dependence of wavelength and polarization. Particularly, the optofluidic beam splitter has advantages such as compact structure and large fabrication tolerance. The proposed device provides a new way to manipulate the optical power splitting, and has wide potential applications in integrated optofluidic system.