Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.

The present disclosure relates to a glass having a refractive index of at least 1.7 as well as the use of the glass as a cladding glass of a solid-state laser. The disclosure also relates to a laser component comprising a core of doped sapphire and a cladding glass being placed on said core. The cladding glass is arranged on said core such that light exiting from the core due to parasitic laser activity can enter the cladding glass and can be absorbed there. Thus, a laser component with improved efficiency is obtained. The present disclosure also relates to a method for producing the laser component.

A method for preparing an erbium (Er)- or erbium oxygen (Er/O)-doped silicon-based luminescent material emitting a communication band at room temperature. The method comprising the following steps: (a) doping a single crystalline silicon wafer with erbium ion implantation or co-doping the single crystalline silicon wafer with erbium ion and oxygen ion implantation simultaneously to obtain an Er- or Er/O-doped silicon wafer, wherein the single crystalline silicon wafer is a silicon wafer with a germanium epitaxial layer, or an SOI silicon wafer with silicon on an insulating layer or other silicon-based wafers; and (b) subjecting the Er- or Er/O-doped silicon wafer to a deep-cooling annealing treatment, the deep-cooling annealing treatment includes a temperature increasing process and a rapid cooling process.

Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.

An optical full-field transmitter for an optical communications network includes a primary laser source configured to provide a narrow spectral linewidth for a primary laser signal, and a first intensity modulator in communication with a first amplitude data source. The first intensity modulator is configured to output a first amplitude-modulated optical signal from the laser signal. The transmitter further includes a first phase modulator in communication with a first phase data source and the first amplitude-modulated optical signal. The first phase modulator is configured to output a first two-stage full-field optical signal. The primary laser source has a structure based on a III-V compound semiconductor.

Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.

Superlattice structures composed of single-crystal semiconductor wells and amorphous barriers are provided. Also provided are methods for fabricating the superlattice structures and electronic, optoelectronic, and photonic devices that include the superlattice structures. The superlattice structures include alternating quantum barrier layers and quantum well layers, the quantum barrier layers comprising an amorphous inorganic material and the quantum well layers comprising a single-crystalline semiconductor.

Superlattice structures composed of single-crystal semiconductor wells and amorphous barriers are provided. Also provided are methods for fabricating the superlattice structures and electronic, optoelectronic, and photonic devices that include the superlattice structures. The superlattice structures include alternating quantum barrier layers and quantum well layers, the quantum barrier layers comprising an amorphous inorganic material and the quantum well layers comprising a single-crystalline semiconductor.

A tunable laser that includes an array of parallel optical amplifiers is described. The laser may also include an intracavity NM coupler that couples power between a cavity mirror and the array of parallel optical amplifiers. Phase adjusters in optical paths between the NM coupler and the optical amplifiers can be used to adjust an amount of power output from M1 ports of the NM coupler. A tunable wavelength filter is incorporated in the laser cavity to select a lasing wavelength.

Provided is a laser device according to an embodiment of the inventive concept. The laser device includes: a semiconductor substrate; a germanium single crystal layer on the semiconductor substrate; and a pumping light source disposed on the germanium single crystal layer and configured to emit light toward the germanium single crystal layer, wherein the germanium single crystal layer receives the light to thereby output laser.