Self-starting bi-chromatic LiNbO<sub>3</sub> soliton microcomb

He, Yang; Yang, Qi‐Fan; Ling, Jingwei; Luo, Rui; Liang, Hanxiao; Li, Mingxiao; Shen, Boqiang; Wang, Heming; Vahala, Kerry J.; Lin, Qiang

doi:10.1364/optica.6.001138

Cited by 346 publications

(226 citation statements)

References 59 publications

Supporting

Mentioning

194

Contrasting

Unclassified

Order By: Relevance

“…4 factors beyond 10 million [18]. Its combined third and second order nonlinearities have also allowed soliton microcomb formation with intrinsic second-harmonic generation [19].However, despite the significant progress, there are still many challenges in the current technologies of integrated nonlinear photonics. One problem is efficiency as measured by threshold or turn-on power.…”

mentioning

confidence: 99%

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

et al. 2020

Self Cite

View full text Add to dashboard Cite

†All three authors contributed equally to this work pg. 2 Recent advances in nonlinear optics have revolutionized the area of integrated photonics, providing on-chip solutions to a wide range of new applications. Currently, the state of the art integrated nonlinear photonic devices are mainly based on dielectric material platforms, such as Si3N4 and SiO2. While semiconductor materials hold much higher nonlinear coefficients and convenience in active integration, they suffered in the past from high waveguide losses that prevented the realization of highly efficient nonlinear processes on-chip. Here we challenge this status quo and demonstrate an ultra-low loss AlGaAs-on-insulator (AlGaAsOI) platform with anomalous dispersion and quality (Q) factors beyond 1.5 × 10 6 . Such a high quality factor, combined with the high nonlinear coefficient and the small mode volume, enabled us to demonstrate a record low Kerr frequency comb generation threshold of ~36 µW for a resonator with a 1 THz free spectral range (FSR), ~100 times lower compared to that in previous semiconductor platform. Combs with >250 nm broad span have been generated under a pump power lower than the threshold power of state of the art dielectric micro combs. A soliton-step transition has also been observed for the first time from an AlGaAs resonator. This work is an important step towards ultra-efficient semiconductor-based nonlinear photonics and will lead to fully integrated nonlinear photonic integrated circuits (PICs) in near future. pg. 3 The extensive research on integrated nonlinear photonics in the last few years, driven by the breakthrough of the microcomb and other on-chip nonlinear devices, has opened up many new opportunities for on-chip integrated photonics, ranging from spectroscopy to atomic clock applications [1-3]. The demand to construct efficient nonlinear devices has motivated the development of different material platforms in nonlinear photonics. A common endeavor of those efforts is the reduction of the waveguide propagation loss, which is essential to enable high Q cavities so as to enhance the build-up power in the resonators and therefore increase the efficiency of the nonlinear optical processes [4]. In this regard, silica on silicon resonators [5-7] have long been dominant offering Q factors as high as 1 billion [6]. These devices can access a wide range of nonlinear effects including microwave rate soliton microcombs [8].However, over the last 5 years, there has been remarkable progress to significantly improve the Q factors of resonators in many other nonlinear integrated optical material platforms. One example is the Si3N4 platform, which delivers high performance in Kerr comb generation on chip [9][10][11]. The Si3N4 micro-resonators have enabled the generation of efficient frequency combs with repetition rates from microwave to THz frequencies [12] and improved Q factor of beyond 30 million [13,14]. Another material, which recently attracted attention, is LiNbO3. It offers additional opportunities for integrated nonlinear...

show abstract

mentioning

confidence: 99%

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Such discrepancy was also observed in previous studies of SHG in whispering gallery mode LN resonators [52,53] and may be attributed to the enhanced photorefractive (PR) effect with the high intracavity power. As the pump power increases, the PR effect induces wavelengthdependent blueshifts of the cavity resonances [32,54], thereby creating a frequency mismatch of the pump and SH resonances, which hinders the maximum obtainable conversion efficiency at a preselected optimal temperature. Further studies will be required to quantify and compensate the PR effect via the dynamical thermal or electrical tuning in order to improve the device performance in the high power regime.…”

Section: Resultsmentioning

confidence: 99%

Periodically poled thin-film lithium niobate microring resonators with a second-harmonic generation efficiency of 250,000%/W

Lu¹,

Surya²,

Liu³

et al. 2019

Optica

336

182

View full text Add to dashboard Cite

Lithium niobate (LN), dubbed by many as the silicon of photonics, has recently risen to the forefront of chip-scale nonlinear optics research since its demonstration as an ultralow-loss integrated photonics platform. Due to its significant quadratic nonlinearity (χ (2) ), LN inspires many important applications such as second-harmonic generation (SHG), spontaneous parametric down-conversion, and optical parametric oscillation. Here, we demonstrate high-efficiency SHG in dual-resonant, periodically poled z-cut LN microrings, where quasi-phase matching is realized by field-assisted domain engineering. Meanwhile, dual-band operation is accessed by optimizing the coupling conditions in fundamental and second-harmonic bands via a single pulley waveguide. As a result, when pumping a periodically poled LN microring in the low power regime at around 1617 nm, an on-chip SHG efficiency of 250,000 %/W is achieved, a state-of-the-art value reported among current integrated photonics platforms. An absolute conversion efficiency of 15% is recorded with a low pump power of 115 µW in the waveguide. Such periodically poled LN microrings also present a versatile platform for other cavity-enhanced quasi-phase matched χ (2) nonlinear optical processes.

show abstract

“…The monolithic lithium niobate on insulator (LNOI) platform has attracted significant interest for realization of next-generation nonlinear photonic devices and observation of new nonlinear dynamics due to its large c (2) (r33 = 3 ´ 10 -11 m/V) and c (3) nonlinearities (n2 = 1.8 ´ 10 -19 m 2 /W) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] . The LNOI platform is opening new opportunities for large-scale integration of optical and electronic devices on a single chip, as it combines the material properties of lithium niobate with the integration power of nano-photonics.…”

Section: Introductionmentioning

confidence: 99%

Raman lasing and soliton mode-locking in lithium niobate microresonators

et al. 2020

View full text Add to dashboard Cite

The recent advancement in lithium niobate on insulator (LNOI) technology is revolutionizing the optoelectronic industry as devices of higher performance, lower power consumption, and smaller footprint can be realized due to the high optical confinement in the structures. The LNOI platform offers both large c (2) and c (3) nonlinearities along with the power of dispersion engineering, enabling brand new nonlinear photonic devices and applications towards the next generation of integrated photonic circuits. However, the Raman scattering, one of the most important nonlinear phenomena, have not been extensively studied, neither was its influences in dispersion-engineered LNOI nano-devices. In this work, we characterize the Raman radiation spectra in a monolithic lithium niobate (LN) microresonator via selective excitation of Raman-active phonon modes. Remarkably, the dominant mode for Raman oscillation is observed in the backward direction for a continuous-wave pump threshold power of 20 mW with a reportedly highest differential quantum efficiency of 46 %. In addition, we explore the effects of Raman scattering on Kerr optical frequency combs generation. We achieve, for the first time, soliton modelocking on a X-cut LNOI chip through sufficient suppression of the Raman effect via cavity geometry control. Our analysis of the Raman effect provides guidance for the development of future chip-based photonic devices on the LNOI platform.

show abstract

Self-starting bi-chromatic LiNbO₃ soliton microcomb

Cited by 346 publications

References 59 publications

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

Periodically poled thin-film lithium niobate microring resonators with a second-harmonic generation efficiency of 250,000%/W

Raman lasing and soliton mode-locking in lithium niobate microresonators

Contact Info

Product

Resources

About

Self-starting bi-chromatic LiNbO3 soliton microcomb

Cited by 346 publications

References 59 publications

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

Periodically poled thin-film lithium niobate microring resonators with a second-harmonic generation efficiency of 250,000%/W

Raman lasing and soliton mode-locking in lithium niobate microresonators

Contact Info

Product

Resources

About

Self-starting bi-chromatic LiNbO₃ soliton microcomb