Yuwen Duan

Time dependent study of femtosecond laser written waveguide lasers in Yb-doped silicate and phosphate glass

Abstract: We study the time dependent performance of distributed feedback (DFB) waveguide lasers (WGLs) fabricated with an ultrafast laser in Yb-doped phosphate and silicate glasses for the first time. After 30 hours of continuous pumping, the phosphate based laser performance degraded while the silicate based laser surprisingly improved in performance. Additional studies of grating behavior during optical pumping imply that the propagation loss for the silicate glass waveguides reduces over time.

Narrow Linewidth DFB Waveguide Laser Fabricated via Ultrafast Laser Inscription

Linewidth measurement of a femtosecond laser direct-written distributed feedback (DFB) waveguide laser (WGL) is reported. The WGL was fabricated in Yb-doped phosphate glass using the femtosecond laser direct-write technique. The linewidth was measured using a loss-compensated recirculating delayed self-heterodyne interferometer. By recirculating the output signal in a 10.2-km fiber delay loop, the linewidth was measured to be 35.4±1.4 kHz at a delay time of 306 μs0 , which is comparable with that of narrow-linewidth fiber DFB lasers.

Generation of heralded single photons beyond 1100 nm by spontaneous four-wave mixing in a side-stressed femtosecond laser-written waveguide

We demonstrate a monolithically integrable heralded photon source in a femtosecond laser direct written glass waveguide. The generation of photon pairs with a wide wavelength separation requires a concomitant large birefringence in the normal dispersion regime. Here, by incorporation of side-stress tracks, we produce a waveguide with a birefringence of

Er3+Active Yb3+Ce3+Co-Doped Fluorozirconate Guided-Wave Chip Lasers

1.64\times~10^{-4}

Ultrafast laser inscribed 3D integrated photonics

and propagation loss as low as 0.21 dB/cm near 980~nm. We measure photon pairs with 300~nm wavelength separation at an internal generation rate exceeding

The influence of distributed rare earth dopant on the performance of waveguide lasers fabricated by the femtosecond laser direct-write technique

5.05\times10^6

Recent developments in dual-wavelength DFB waveguide lasers fabricated by femtosecond laser pulses

/s. The second order correlations indicate that the generated photon pairs are in a strongly non-classical regime.

Theoretical modeling and experiments on a DBR waveguide laser fabricated by the femtosecond laser direct-write technique

We report efficient 1.55-μm laser operation in a waveguide chip laser femtosecond-laser inscribed in bulk fluorozirconate glass. The ternary doped glass is composed of erbium as the active laser ion, ytterbium sensitizer, and cerium to enhance the branching ratio from the pump to the erbium upper laser state. We have achieved slope efficiencies up to 25%, with a low 100-mW threshold. To meet diverse application requirements, we also report the wide tunability of 1507-1593 nm, and large single-transverse-mode Gaussian beam-output from the 55 μm diameter waveguides.

Comparison study of femtosecond direct-written monolithic waveguide lasers in Yb-doped silicate and phosphate glass

Since the discovery, that a tightly focused femtosecond laser beam can induce a highly localized and permanent refractive index change in a wide range of dielectrics, ultrafast laser inscription has found applications in many elds due to its unique 3D and rapid prototyping capabilities. These ultrafast laser inscribed waveguide devices are compact and lightweight as well as inherently robust since the waveguides are embedded within the bulk material. In this presentation we will review our current understanding of ultrafast laser - glass lattice interactions and its application to the fabrication of inherently stable, compact waveguide lasers and astronomical 3D integrated photonic circuits.

Narrow linewidth DFB waveguide laser fabricated via ultrafast laser inscription

The development of an Yb-doped distributed Bragg reflector (DBR) waveguide laser fabricated in phosphate glass using the femtosecond laser direct-write technique is reported. The laser has the slope efficiency of 31% with the output power up to 81 mW at a pump power level of 378 mW. A theoretical model for the waveguide laser (WGL) is presented which gives emphasis to transverse integrals to investigate the energy distribution in a homogenously doped glass which is opposed to the fiber laser. The model was validated with experiments comparing a DBR WGL, and then used to study the influence of distributed rare earth dopants on the performance of such lasers. Approximately 15% of the pump power was absorbed by the doped “cladding” in the femtosecond laser inscribed Yb doped WGL case.