Self-Injection Locking of a Gain-Switched Laser Diode

Galiev

Min’kov

et al. 2023

Preprint

Narrow-linewidth lasers are in extensive demand for numerous cutting-edge applications. Such lasers operating at the visible range are of particular interest. Self-injection locking of a laser diode frequency to a high-Q whispering gallery mode is an effective and universal way to achieve superior laser performance. We demonstrate ultrastable lasing with less than 10 Hz instantaneous linewidth for 20 μs averaging time at 638 nm using a Fabry-Pérot laser diode locked to a crystalline MgF2 microresonator. The linewidth measured with a β-separation line technique that characterizes 10 ms stability is as low as 850 Hz. Output power exceeds 80 mW. Demonstrated results are among the best for compact visible-range lasers in terms of stability and output power. We additionally report the first demonstration of a gain-switched regime for such stabilized Fabry-Pérot laser diode showing a high-contrast visible frequency comb generation. Tunable linespacing from 10 MHz to 2 GHz is observed. We demonstrated that the beatnote between the lines has sub-Hz linewidth and experiences spectral purification in the self-injection locking regime. This result might be of special importance for spectroscopy in the visible range.

Section: /10mentioning

confidence: 95%

Section: /10mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Red narrow-linewidth lasing and frequency comb from gain-switched self-injection-locked Fabry-Pérot laser diode

Galiev

Min’kov

et al. 2023

Preprint

“…Microresonator-based stabilization allows laser operation in the gain-switching (GS) regime 39 , 40 . Gain switching via modulation of a laser diode operating current through a bias tee circuit allows for the generation of a frequency comb with line spacing defined by the microwave modulation frequency 41 – 43 .…”

Section: Introductionmentioning

confidence: 99%

Red narrow-linewidth lasing and frequency comb from gain-switched self-injection-locked Fabry–Pérot laser diode

Galiev

Min’kov

et al. 2023

Sci Rep

Self Cite

Narrow-linewidth lasers are in extensive demand for numerous cutting-edge applications. Such lasers operating at the visible range are of particular interest. Self-injection locking of a laser diode frequency to a high-Q whispering gallery mode is an effective and universal way to achieve superior laser performance. We demonstrate ultranarrow lasing with less than 10 Hz instantaneous linewidth for 20 $$\mu$$ μ s averaging time at 638 nm using a Fabry–Pérot laser diode locked to a crystalline MgF$$_2$$ 2 microresonator. The linewidth measured with a $$\beta$$ β -separation line technique that characterizes 10 ms stability is as low as 1.4 kHz. Output power exceeds 80 mW. Demonstrated results are among the best for visible-range lasers in terms of linewidth combined with solid output power. We additionally report the first demonstration of a gain-switched regime for such stabilized Fabry–Pérot laser diode showing a high-contrast visible frequency comb generation. Tunable linespacing from 10 MHz to 3.8 GHz is observed. We demonstrated that the beatnote between the lines has sub-Hz linewidth and experiences spectral purification in the self-injection locking regime. This result might be of special importance for spectroscopy in the visible range.

“…Optical microresonators with whispering gallery modes (WGM) are budding for the mid-IR photonic devices development for both fundamental and applied problems. 1,2 The advantage of combination of the small mode volume and high quality factor allows to produce successfully compact high-performance devices for a wide range of applications and devices such as for stabilization of the laser and narrow linewidth lasers, [3][4][5][6] chemical and biological sensing, [7][8][9] nonlinear optical devices, [10][11][12] spectroscopy. 13 The Er:ZBLAN microspheres used in the previously mentioned study were made by the method described in.…”

Section: Introductionmentioning

confidence: 99%

High-Q WGM microresonators for mid-IR

Tebeneva

Nanophotonics, Micro/Nano Optics, and Plasmonics VIII

Benderov

et al. 2023

We upgraded the original fabrication method based on melting commercially available ZBLAN (heavy metal fluoride glass) optical fiber to obtain high-quality-factor ZBLAN microspheres with a diameter of 250 to 400 µm. The whispering gallery modes were excited in fabricated microresonators by different coupling elements and the high Q-factors at both 1.55 µm and 2.64 µm were demonstrated. At 1.5 µm the intrinsic Q-factor of (5.4 ± 0.4) • 10 8 determined by material losses was obtained. For 2.64 µm the quality factor was measured as (1.13 ± 0.22) • 10 8 .