Search

This article presents a dual-wavelength signal wave output system capable of generating a broad range of adjustable wavelength intervals. The setup involved the creation of a dual-wavelength cascaded Raman laser featuring composite cavities operating at 1176 nm and 1313 nm. Experimental investigations were carried out on an external cavity MgO:PPLN-OPO driven by the cascaded Raman laser. By setting the crystal polarization period to 27.6-34.4 µm and the temperature to 50-130°C, adjustable tunable output of dual-wavelength signal wave at 1176 nm-MgO:PPLN-OPO (1550-2294 nm) and 1313 nm-MgO:PPLN-OPO (1768-2189 nm) was achieved with a wavelength interval of 0-218 nm. Under the conditions of a period of 34.4 µm, temperature of 90°C, and an incident Raman power of 2.6 W, the highest conversion efficiency of Raman to dual-wavelength signal wave (2212, 2182 nm) was 34.2%. Furthermore, the maximum output power of dual-wavelength signal wave was recorded at 1.02 W with an incident Raman power of 3.33 W.

Photonic heterostructure has recently become a promising platform to study topological photonics with the introduction of mode width degree of freedom (DOF). However, there is still a lack of comprehensive analysis on the coupling of dipole emitters in photonic heterostructures, which constrains the development of on-chip quantum optics based on chiral dipole sources. We systematically analyze the unidirectional coupling mechanism between dipole emitters and valley photonic heterostructure waveguides (VPHWs). With the eigenmode calculations and full-wave simulations, the Stokes parameters are obtained to compare the coupling performance of two types of valley-interface VPHWs. Simulation results show that compared to the zigzag interface with inversion symmetry, the strategy of bearded interface with glide symmetry is easier to realize high-efficiency coupling. By adjusting the position and chirality of dipole emitters in VPHWs, the transmission of light reverses with guided modes coupled to different directions. Furthermore, a topological beam modulator is realized based on VPHWs, which maintains the robustness to large-area potential barriers and sharp corners. Our work supplies a powerful guide for chiral light-matter interaction, which is expected to be applied to increasingly compact and efficient on-chip optical platforms in the future.

We report an actively Q-switched Nd:YVO 4 /YVO 4 intracavity Raman laser at second-Stokes wavelength of 1313.6 nm, which is capable of operating efficiently under pulse repetition frequency higher than 80 kHz. A folded coupled cavity is adopted to optimize the fundamental and the Stokes resonators individually and make full use of the high pump intensity on the Raman crystal. With relatively high output coupling of 82% at 1313 nm, the average output power of 5.16 W at 1313 nm is achieved under the incident pump power of 36.7 W. The cascaded Raman emission at both the first- and second-Stokes wavelength of 1176 and 1313 nm is investigated to discuss the optimization of the second-Stokes generation.

Here we propose an efficient diode-end-pumped actively Q-switched 1176-nm Nd:YAG/Nd:YVO 4 hybrid gain intracavity Raman laser. By virtue of the construction of a coaxial double crystal, the laser not only can operate efficiently at low pulse repetition frequencies (PRFs), thereby realizing relatively high-energy and high-peak-power pulsed output, but also is capable of generating a high average output power at high PRFs. A maximum pulse energy of 0.54 mJ for the 1176-nm Stokes light is achieved at the PRF of 10 kHz, and the maximum average output power up to 9.80 W is obtained at the PRF of 100 kHz, while the incident pump power is 42.0 W.

We report herein an efficient eye-safe Raman laser, which is based upon Nd:YVO₄₋YVO₄ and in-band pumped by a wavelength-locked laser diode array at 878.6 nm. By virtue of mitigated thermal load and improved pump absorption, a maximum average output power of 5.2 W at 1525 nm is obtained under the incident pump power of 30.6 W with the pulse repetition frequency of 140 kHz, corresponding to an optical efficiency of 17.0%.