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Abstract Integrated electro-optic (EO) modulators are fundamental photonics components with utility in domains ranging from digital communications to quantum information processing. At telecommunication wavelengths, thin-film lithium niobate modulators exhibit state-of-the-art performance in voltage-length product (VπL), optical loss, and EO bandwidth. However, applications in optical imaging, optogenetics, and quantum science generally require devices operating in the visible-to-near-infrared (VNIR) wavelength range. Here, we realize VNIR amplitude and phase modulators featuringVπL’s of sub-1 V ⋅ cm, low optical loss, and high bandwidth EO response. Our Mach-Zehnder modulators exhibit aVπLas low as 0.55 V ⋅ cm at 738 nm, on-chip optical loss of ~0.7 dB/cm, and EO bandwidths in excess of 35 GHz. Furthermore, we highlight the opportunities these high-performance modulators offer by demonstrating integrated EO frequency combs operating at VNIR wavelengths, with over 50 lines and tunable spacing, and frequency shifting of pulsed light beyond its intrinsic bandwidth (up to 7x Fourier limit) by an EO shearing method.
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DC-stable electro-optic modulators using thin-film lithium tantalate
We demonstrate telecommunication-wavelength Pockels electro-optic modulators in thin-film lithium tantalate (TFLT) with superior DC stability compared to equivalent thin-film lithium niobate (TFLN) modulators. Less than 1 dB output power fluctuation for quadrature-biased TFLT is measured compared to 5 dB with TFLN over 46 hours with 12.1 dBm input power. Our TFLT modulators maintain properties similar to those in TFLN: 3.4 Vcm half-wave voltage length product, 39 dB extinction ratio, flat RF electro-optic response from 3-50 GHz, and 0.35 dB on-chip loss. We also show low error-rate data modulation over 0-70°C with TFLT modulators and optical loss of 9 dB/m.
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- Award ID(s):
- 2138068
- PAR ID:
- 10555758
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 32
- Issue:
- 25
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 44115
- Size(s):
- Article No. 44115
- Sponsoring Org:
- National Science Foundation
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