title: Ultra-broadband high-performance polarizing beam splitter on silicon.
abstract: A high-performance silicon-based polarizing beam splitter (PBS) is proposed and demonstrated experimentally by using an improved structure with cascaded bent directional couplers. The measured extinction ratio (ER) is >35dB and the excess losses (EL) is <0.35dB around the central wavelength for both polarizations. The present PBS has a compact footprint of ~6.9 × 20μm2. The measured bandwidths for an ER of >20dB, >25dB and >30dB are ~135nm, ~95nm and ~70nm, respectively, while the measured EL is <1dB and <0.5dB in a bandwidth of ~140nm and ~85nm, respectively. The fabrication tolerance of the core-width variation is as large as ± 40nm, which makes the fabrication very easy.
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
authors.forename: Ying
authors.initials: Y
authors.lastname: Tan
authors.forename: Daoxin
authors.initials: D
authors.lastname: Dai