TY - JOUR
T1 - Integrated gallium phosphide nonlinear photonics
AU - Wilson, Dalziel J.
AU - Schneider, Katharina
AU - Hönl, Simon
AU - Anderson, Miles
AU - Baumgartner, Yannick
AU - Czornomaz, Lukas
AU - Kippenberg, Tobias J.
AU - Seidler, Paul
N1 - Funding Information:
We thank P. Welter, H. Hahn, U. Drechsler, D. Caimi and A. Olziersky for their valuable contributions to development of the GaP-on-insulator platform. We also thank M. Karpov and T. Herr for useful discussions about frequency comb generation. This work was supported by the European Union’s Horizon 2020 Programme for Research and Innovation under grants 722923 (Marie Curie H2020-ETN OMT) and 732894 (FET Proactive HOT). All samples were fabricated at the Binnig and Rohrer Nanotechnology Center (BRNC) at IBM Research – Zurich.
Publisher Copyright:
© 2019, The Author(s), under exclusive licence to Springer Nature Limited.
PY - 2020/1/1
Y1 - 2020/1/1
N2 - Gallium phosphide (GaP) is an indirect-bandgap semiconductor used widely in solid-state lighting. Despite numerous intriguing optical properties—including large χ(2) and χ(3) coefficients, a high refractive index (>3) and transparency from visible to long-infrared wavelengths (0.55–11 μm)—its application as an integrated photonics material has been little studied. Here, we introduce GaP-on-insulator as a platform for nonlinear photonics, exploiting a direct wafer-bonding approach to realize integrated waveguides with 1.2 dB cm−1 loss in the telecommunications C-band (on par with Si-on-insulator). High-quality (Q > 105), grating-coupled ring resonators are fabricated and studied. Employing a modulation transfer approach, we obtain a direct experimental estimate of the nonlinear index of GaP at telecommunication wavelengths: n2 = 1.1(3) × 10−17 m2 W−1. We also observe Kerr frequency comb generation in resonators with engineered dispersion. Parametric threshold powers as low as 3 mW are realized, followed by broadband (>100 nm) frequency combs with sub-THz spacing, frequency-doubled combs and, in a separate device, efficient Raman lasing. These results signal the emergence of GaP-on-insulator as a novel platform for integrated nonlinear photonics.
AB - Gallium phosphide (GaP) is an indirect-bandgap semiconductor used widely in solid-state lighting. Despite numerous intriguing optical properties—including large χ(2) and χ(3) coefficients, a high refractive index (>3) and transparency from visible to long-infrared wavelengths (0.55–11 μm)—its application as an integrated photonics material has been little studied. Here, we introduce GaP-on-insulator as a platform for nonlinear photonics, exploiting a direct wafer-bonding approach to realize integrated waveguides with 1.2 dB cm−1 loss in the telecommunications C-band (on par with Si-on-insulator). High-quality (Q > 105), grating-coupled ring resonators are fabricated and studied. Employing a modulation transfer approach, we obtain a direct experimental estimate of the nonlinear index of GaP at telecommunication wavelengths: n2 = 1.1(3) × 10−17 m2 W−1. We also observe Kerr frequency comb generation in resonators with engineered dispersion. Parametric threshold powers as low as 3 mW are realized, followed by broadband (>100 nm) frequency combs with sub-THz spacing, frequency-doubled combs and, in a separate device, efficient Raman lasing. These results signal the emergence of GaP-on-insulator as a novel platform for integrated nonlinear photonics.
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U2 - 10.1038/s41566-019-0537-9
DO - 10.1038/s41566-019-0537-9
M3 - Article
AN - SCOPUS:85075459478
SN - 1749-4885
VL - 14
SP - 57
EP - 62
JO - Nature Photonics
JF - Nature Photonics
IS - 1
ER -