Plasmonic loss-mitigating broadband adiabatic polarizing beam splitter

The intriguing analogy between quantum physics and optics has inspired the design of unconventional integrated photonics devices. In this paper, we numerically demonstrate a broadband integrated polarization beam splitter (PBS) by implementing the stimulated Raman adiabatic passage (STIRAP) technique in a three-waveguide plasmonic system. Our proposed PBS exhibits >250 nm transverse-magnetic (TM) bandwidth with <-40 dB extinction and >150 nm transverse-electric (TE) bandwidth with <-20 dB extinction, covering the entire S-, C-, and L-bands and part of the E-band. Moreover, near-lossless light transfer is achieved in our system despite the incorporation of a plasmonic hybrid waveguide because of the unique loss mitigating feature of the STIRAP scheme. Through this approach, various broadband integrated devices that were previously impossible can be realized, which will allow innovation in integrated optics.