Efficient electro-optical tuning of an optical frequency microcomb on a monolithically integrated high-Q lithium niobate microdisk

Abstract

We demonstrate efficient tuning of a monolithically integrated lithium niobate microdisk (LN) optical frequency microcomb. Utilizing the high optical quality (Q) factor (i.e., Q~7.1×10 6 ) of the microdisk, the microcomb spans over a spectral bandwidth of ~200 nm at a pump power as low as 20.4 mW. Combining the large eletrooptic coefficient of LN and optimum design of the geometry of microelectrodes, we demonstrate electro-optical tuning of the comb with a spectral range of 400 pm and a tuning efficiency of ~38 pm/100V.

All-Fiber Hyperparametric Generation Based on a Monolithic Fiber Fabry–Pérot Microresonator

“…The 30-dB bandwidth is less than 100 nm, which is much narrower than the experimental Raman-assisted hyperparametric generation. Raman-induced spectral broadening for Kerr combs in microresonators has been demonstrated in several recent works [16,21,24]; this results from the complex interplay between Kerr, Raman, and all-order dispersion. broadening for Kerr combs in microresonators has been demonstrated in several recent works [16,21,24]; this results from the complex interplay between Kerr, Raman, and all-order dispersion.…”

“…The OFC source based on FWM in Kerr microresonators is a promising candidate for a compact optical frequency standard [8,9,14]. The strong mode confinement and high finesse of microresonators enhance the nonlinear interactions in the FWM process, which have been demonstrated in a large number of platforms such as microrings [15], microdisks [16], and microspheres [17]. However, the quality factor (Q) of these chip-scale microresonators is mainly limited by the propagation loss resulting from surface roughness and material absorption [18].…”

“…All in all, driven by a cw pump laser, FWM can be generated from our FFP microresonator with a fine spectrum tooth of 667 MHz. With the assistance of stimulated Raman scattering in the FFP microresonator [16,20,21], the spectral span is further extended to over 400 nm. It is worth noting that such broadband hyperparametric generation with sub-gigahertz line-to-line frequency separation is rarely achieved in a microresonator due to its propagation-limited Q, as mentioned above.…”

Electro-optically tunable microdisk laser on Er3+-doped lithium niobate thin film

“…The on-chip Er 3 -doped LN microdisk resonator integrated with Cr film electrodes was fabricated by PLACE, and more fabrication details can be found in Refs. [20][21][22]. Figure 1(a) presents the schematic of the on-chip Er 3 -doped LN microdisk resonator integrated with Cr film electrodes.…”

Efficient light coupling between an ultra-low loss lithium niobate waveguide and an adiabatically tapered single mode optical fiber

“…In recent years, photonic devices based on LNOI, including waveguides [6,7], microring resonators [1,8], microdisk resonators [9][10][11], and photonic crystal cavities [12,13] have been developed. On-chip functionalities, such as second harmonic generation [13][14][15][16][17][18], electro-optic modulator [3,[19][20][21][22][23], and optical frequency comb [24,25], have experienced rapid progress with the above-mentioned LNOI micro-/nanodevices. Importantly, many integrated on-chip lithium niobate (LN) devices developed recently already feature low propagation losses [6][7][8]10], which is critical for practical applications.…”