Engineered Raman Lasing in Photonic Integrated Chalcogenide Microresonators

Abstract

Photonic integrated Raman lasers have extended the wavelength range of chip-scale laser sources and have enabled applications including molecular spectroscopy, environmental analysis, and biological detection. Yet, the performance is strongly determined by the pumping condition and Raman shift value of nonlinear medias, leaving challenges to have a widely and continuously tunable Raman laser (e.g., over 100 nm). Here, photonic engineered Raman lasers based on chip-integrated chalcogenide microresonators are demonstrated. The home-developed chalcogenide photonic platform is of high nonlinearity, wide transparency, and low loss. The strong and broadband material Raman response has promised rich dynamics of Raman lasing. Indeed, both single-mode Raman lasing and a broadband Raman-Kerr comb, which are found engineered by tuning the dispersion of the chalcogenide microresonator, are demonstrated. The single-mode Raman laser, together with its cascaded modes, supports a gap-free tuning range over 140 nm, while the threshold power is as low as 3.25 mW. The results may contribute to the understanding of Raman and Kerr nonlinear interactions in dissipative and nonlinear microresonators, and on application aspect, may pave a way to integrated and efficient laser sources that is desired in spectroscopic applications in the infrared.

Soliton microcombs in whispering gallery mode crystalline resonators with broadband intermode interactions

“…Effects of broadband intermode interactions are experimentally evidenced, which would not only tailor the soliton comb spectrum, but also enhance the soliton power efficiency. We also demonstrate soliton combs in company with the Raman lasing, including both narrow-band lasers and Raman-Kerr combs [51][52][53][54], and a suspect Raman-soliton comb [55,56] around the anti-stokes mode. The transmission of the resonance that is pumped and scanned by an intense cw laser, in which the stair-like pattern (soliton steps) indicates the formation of dissipative solitons in the cavity.…”

Transverse mode interaction-induced Raman laser switching dynamics in a silica rod microresonator

“…Microcavitybased Raman lasers have been experimentally realized in silica microcavities [8,9] , silicon racetrack resonators [5,10] , fluoride resonators [11,12] , titanium-sensitized silica microresonators [13] , and on-chip diamond resonators [4] . More recently, widely tunable Raman lasers have also been demonstrated in chip-integrated chalcogenide microresonators, rendering the microcavity-based Raman lasers very promising [14] . Such nonlinear microcavities are an attractive platform, allowing for potential applications as compact switchable laser sources, optical clocks, and spectroscopic sensing [15][16][17][18][19] .…”

Thermo-Optical Sensitivity of Whispering Gallery Modes in As2S3 Chalcogenide Glass Microresonators

“…Chalcogenide glasses have been actively investigated for implementing nonlinear optical effects, since such glasses have huge cubic nonlinearities, ultrawide transparency ranges, and physical and chemical properties suitable for producing optical microresonators. For example, Raman lasing [19,20], optical parametric oscillations [21], the generation of Raman-Kerr optical frequency combs [22], and Brillouin generation [23] have been attained in chalcogenide microresonators.…”

“…For instance, a laser wavelength in an Nd-doped chalcogenide microsphere was tuned when the pump power was changed; this fact was explained by the influence of nonlinear and/or thermal effects [25]. In [22], the tunability of a Raman wavelength was obtained with a change in temperature due to shifts of the WGM resonances.…”