Phase change materials (PCMs) have long been used as a storage medium in rewritable compact disk and later in random access memory. In recent years, integration of PCMs with nanophotonic structures has introduced a new paradigm for non‐volatile reconfigurable optics. However, the high loss of the archetypal PCM Ge2Sb2Te5in both visible and telecommunication wavelengths has fundamentally limited its applications. Sb2S3has recently emerged as a wide‐bandgap PCM with transparency windows ranging from 610 nm to near‐IR. In this paper, the strong optical phase modulation and low optical loss of Sb2S3are experimentally demonstrated for the first time in integrated photonic platforms at both 750 and 1550 nm. As opposed to silicon, the thermo‐optic coefficient of Sb2S3is shown to be negative, making the Sb2S3–Si hybrid platform less sensitive to thermal fluctuation. Finally, a Sb2S3integrated non‐volatile microring switch is demonstrated which can be tuned electrically between a high and low transmission state with a contrast over 30 dB. This work experimentally verifies prominent phase modification and low loss of Sb2S3in wavelength ranges relevant for both solid‐state quantum emitter and telecommunication, enabling potential applications such as optical field programmable gate array, post‐fabrication trimming, and large‐scale integrated quantum photonic network.
- Award ID(s):
- 1640196
- NSF-PAR ID:
- 10184044
- Date Published:
- Journal Name:
- Techcon 2018
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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