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Current integrated optical isolators have limited bandwidths due to stringent phase-matching, resonant structures, or absorption. We demonstrate broadband optical isolation in thin-film lithium niobate that simultaneously achieves∼100 nm isolation bandwidth at visible and telecom wavelengths.
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Visible-telecom tunable dual-band optical isolator based on dynamic modulation in thin-film lithium niobate
Optical isolators are an essential component of photonic systems. Current integrated optical isolators have limited bandwidths due to stringent phase-matching conditions, resonant structures, or material absorption. Here, we demonstrate a wideband integrated optical isolator in thin-film lithium niobate photonics. We use dynamic standing-wave modulation in a tandem configuration to break Lorentz reciprocity and achieve isolation. We measure an isolation ratio of 15 dB and insertion loss below 0.5 dB for a continuous wave laser input at 1550 nm. In addition, we experimentally show that this isolator can simultaneously operate at visible and telecom wavelengths with comparable performance. Isolation bandwidths up to ∼100 nm can be achieved simultaneously at both visible and telecom wavelengths, limited only by the modulation bandwidth. Our device’s dual-band isolation, high flexibility, and real-time tunability can enable novel non-reciprocal functionality on integrated photonic platforms.
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- Award ID(s):
- 1907918
- PAR ID:
- 10405055
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 48
- Issue:
- 8
- ISSN:
- 0146-9592; OPLEDP
- Format(s):
- Medium: X Size: Article No. 1978
- Size(s):
- Article No. 1978
- Sponsoring Org:
- National Science Foundation
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