A New Family of Ultralow Loss Reversible Phase‐Change Materials for Photonic Integrated Circuits: Sb 2 S 3 and Sb 2 Se 3

Abstract Phase‐change materials (PCMs) are seeing tremendous interest for their use in reconfigurable photonic devices; however, the most common PCMs exhibit a large absorption loss in one or both states. Here, Sb 2 S 3 and Sb 2 Se 3 are demonstrated as a class of low loss, reversible alternatives to the standard commercially available chalcogenide PCMs. A contrast of refractive index of Δ n = 0.60 for Sb 2 S 3 and Δ n = 0.77 for Sb 2 Se 3 is reported, while maintaining very low losses ( k < 10 −5 ) in the telecommunications C‐band at 1550 nm. With a stronger absorption in the visible spectrum, Sb 2 Se 3 allows for reversible optical switching using conventional visible wavelength lasers. Here, a stable…

• EA
  Engineering and Physical Sciences Research Council

  Awards: EP/M009122/1, EP/M015130/1, EP/G060363/1, EP/L021129/1, EP/L021129/1, EP/G060363/1, EP/M009122/1, EP/J016918/1, EP/T019697/1, EP/M015130/1