A two-color visible frequency comb system based on a 1.5-μm all-polarization-maintaining (PM) fiber femtosecond laser was developed. This configuration relies on the implementation of three amplifiers, seeded by a single master oscillator. With the repetition rate (fr) of the oscillator locked to a reference frequency of 200 MHz, the output of the first amplifier was used to generate the feedback signal and achieve simultaneous phase lock of the carrier envelop offset frequency (fceo). The remaining two independently configurable amplifiers followed by highly nonlinear fibers and MgO-doped periodically poled lithium niobite crystals were used to produce visible comb lights at 543 and 633 nm (in air), respectively. By referencing to a hydrogen maser, the Allan deviations of fr and fceo at a gate time of 1 s are 438 μHz and 63 mHz, respectively. The spectral bandwidths of the 543- and 633-nm comb lights are 0.157 and 0.174 nm, respectively, and the single-mode powers of these comb lights are higher than 1 μW. The multiple-branch all-PM fiber-based visible frequency comb system exhibiting a narrow spectrum and a high single-mode power will facilitate the development of optical clocks and wavelength standard calibrations.
We demonstrate a 200-MHz all polarization-maintaining, repetition-rate-locked femtosecond fiber laser system with a total electrical power consumption of 11 W. The center wavelength, spectral width, pulse width, and average output power of the laser are 1558.8 nm, 34 nm, 139 fs, and 77.6 mW, respectively. The proposed laser system that integrates all optical components and locking electronics has a volume less than 1.5 L, a mass of 1.3 kg, and a fast locking time of 3 s (from the free running state to the repetition-rate-locked state). Using a hydrogen maser as the frequency reference, after locking, the Allan deviation is 2.8 mHz at a gate time of 1 s. Further, we place the repetition-rate-locked fiber laser system on a homemade shaker table with peak and rms accelerations of 1.97 and 0.7 g, respectively; the experimental results show that the locking state can be maintained robustly with Allan deviation of 2.0 mHz. The highly integrated, robust fiber laser system has potential applications in the areas of ultralow-noise microwave generation and high-precision distance measurement in outdoor environments.
Based on the scalar four-photon scattering process, the quantum state of a lightwave at the output of fiber is derived by solving the nonlinear Schrödinger equation with a perturbation theory. The joint spectral function of two photons is achieved from the derived quantum state. The dispersion operator involves the third-order dispersion term in the case that the pump wavelength is close to the zero dispersion wavelength. Simulation results show the first-order approximation of our joint spectral function is in excellent agreement with the complicated exact solution. By analyzing the spectral property of the two-photon flux generated by four-photon scattering in photonic-crystal fibers, it is found that the sign of dispersion has very little influence on the spectrum except the slight modulation instability in the anomalous dispersion domain.
Switchable multiwavelength fiber laser outputs with a wide tuning range are experimentally observed in an ultralong cavity. Because of the long spooled single-mode fiber and filter effect of the cavity, multiwavelength lasers with the spacing of ~14.5 nm are obtained. The proposed fiber laser has the capacity of simultaneously emitting the three wavelengths. By means of adjusting the polarization controllers, the arbitrary single- and dual-wavelength operations are achieved in our laser.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.