A new green-emitting phosphor, KAlSiO₄:1.5 mol% Tb³⁺, x mol% Li⁺, was prepared via a high-temperature solid-phase method, and its crystal structure, diffuse reflectance spectrum, and luminescence were studied. The results show that the Li⁺ doping shifts the strongest diffraction peak to a high angle direction, reducing grain size by 11.4%. The entry of Li₂CO₃ improves the luminescence performance of KAlSiO₄:1.5 mol% Tb³⁺. At a Li⁺ concentration of 1.5 mol%, the sample has strong absorption in the ultraviolet light range from 250 to 400 nm. The luminous intensity of the sample at 550 nm approximately quadruples after Li⁺ doping. Additionally, the colour purity of the sample and the internal quantum yield increase to 83.3% and 42%, respectively. The sample changes colour with time when exposed to air without an obvious fading phenomenon. The emission intensity at 200 °C is 95.1% of its value at room temperature, indicating that the phosphor has excellent thermal stability when x = 1.5. These results show the feasibility of using the silicate phosphor for generating the green light component of white light-emitting diodes for solid-state lighting.

We investigated high energy, near and mid-infrared optical vortex lasers formed by a 1 μm optical vortex-pumped KTiOAsO₄ (KTA) optical parametric oscillator. The orbital angular momentum (OAM) of the pump beam can be selectively transferred to the signal or idler output by changing the reflectivity of the output coupler. With this system, 1.535 µm vortex signal output with an energy of 2.04 mJ and 3.468 µm vortex idler output with an energy of 1.75 mJ were obtained with a maximum pump energy of 21 mJ, corresponding to slope efficiencies of 14% and 10%, respectively. The spectral bandwidth (full width at half maximum, FWHM) of the signal and idler vortex outputs were measured to be Δλ_s ~ 1.3 nm (~ 5.5 cm⁻¹) and Δλ_i ~ 1.7 nm (~ 1.4 cm⁻¹), respectively.

State preparation via postselected weak measurements in a three-wave mixing process is studied. We assume the signal input mode is prepared in a vacuum state, coherent state, or squeezed vacuum state, while the idler input is prepared in a weak coherent state and passes the medium characterized by the second-order nonlinear susceptibility. It is shown that when the single photon is detected at one of the output channels of the idler beam's path, the signal output channel is prepared in a single-photon Fock state, single-photon-added coherent state, or single-photon-added squeezed vacuum state with very high fidelity, depending upon the input signal states and related controllable parameters. The properties of squeezing, signal amplification, second-order correlation, and the Wigner functions of the weak-measurement-based output states are also investigated. Our scheme promises to provide an alternate effective method for producing useful nonclassical states in quantum information processing.

This work report the generation of high‐order Laguerre–Gaussian (LG) modes from a nanosecond, optical vortex pumped diamond Raman laser. This system is capable of generating first‐Stokes (λ_1st = 1240 nm) LG modes with topological charge (ℓ) of up to 26 and second‐Stokes (λ_2nd = 1485 nm) LG modes with topological charge of up to 22, when pumped using a first‐order vortex beam. The maximum first‐ and second‐Stokes LG mode energies are measured to be 0.5 and 1 mJ, respectively, when pumping with energy of 19.8 mJ.