In various embodiments, an emission source may be provided. The emission source may also include a gain medium including a halide semiconductor material. The emission source may further include a pump source configured to provide energy to the gain medium. The halide semiconductor material may include a lead-free perovskite material.

Core-cladding planar waveguide (PWG) structures and methods of making and using same. The core-cladding PWG structures can be synthesized by hydride vapor phase epitaxy and processed by mechanical and chemical-mechanical polishing. An Er doping concentration of [Er] between 110.sup.18 atoms/cm.sup.3 and 110.sup.22 atoms/cm.sup.3 can be in the core layer. Such PWGs have a core region that can achieve optical confinement between 96% and 99% and above.

An optical parametric device (OPD), which is selected from an optical parametric oscillator (OPO) or optical parametric generator (OPG), is configured with a nonlinear optical element (NOE) which converts an incoupled pump radiation at first frequency into output signal and idler radiations at one second frequency or different second frequencies, which is/are lower than the first frequency, by utilizing nonlinear interaction via a random quasi-phase matching process (RQPM-NOE). The NOE is made from a nonlinear optical material selected from optical ceramics, polycrystals, micro and nanocrystals, colloids of micro and nanocrystals, and composites of micro and nanocrystals in polymer or glassy matrices. The nonlinear optical material is prepared by modifying a microstructure of the initial sample of the NOE such that an average grain size is of the order of a coherence length of the three-wave interaction which enables the highest parametric gain achievable via the RQPM process.

A first layer, a first spacer layer, and a second layer of a semiconductor wafer can be etched to produce a plurality of columnar structures extending from the substrate layer and including a first optical cavity situated about the first gain medium, a second optical cavity situated about the second gain medium, and a first spacer region contacting the first gain medium and the second gain medium. Also, a photonic microparticle formed from a layered semiconductor wafer and of a columnar structure having a first optical cavity situated about a first gain medium, a second optical cavity situated about a second gain medium, and a first spacer region contacting the first gain medium and the second gain medium. The first optical cavity and the second optical cavity in the photonic microparticle are each capable of generating laser light with a distinct spectral peak when energetically excited.

Hybrid silicon devices are disclosed in which a silicon-based resonant structure is coated with a rare-earth-doped tellurium oxide layer that facilitates optical gain, thereby forming a silicon-based laser cavity. The silicon-based laser cavity supports at least one resonant mode that has a modal volume extending from the silicon resonant base structure into the rare-earth-doped tellurium oxide layer. The silicon-based laser cavity is optically coupled to a silicon waveguide to facilitate the delivery of pump laser energy to the silicon-based laser cavity, such that at least a portion of the pump laser energy propagating through the silicon waveguide is coupled to the silicon-based laser cavity for excitation of the rare earth dopant within the rare-earth-doped tellurium oxide layer. The silicon waveguide that is optically coupled to the silicon-based laser cavity also facilitates the external delivery of the laser energy generated within silicon-based laser cavity.

Self-isolated lasers are provided by using a chiral metasurface in combination with a spin-selective gain medium and symmetry-breaking (i.e., not linearly polarized) optical pumping. In preferred embodiments the chiral metasurface is resonant, thereby proving an integrated optical resonator to support lasing. The chiral metasurface can be the spin-selective gain medium, or it can be formed on a surface of the spin-selective gain medium, or it can be distinct from the spin-selective gain medium.