Abstract: 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.

Abstract: Grooves (22, 23) for containing an optical fiber and five recesses (24) for containing the optical components for an optical fiber amplifier are provided in the surface of a substrate (21). An optical fiber fitted in a groove (23a) for containing the optical fiber and introduced to the substrate (21) is passed through a groove (22a) for containing the optical fiber and fitted in a groove (22) for containing the optical fiber, thence passed through a groove (22b) for containing the optical fiber and introduced to the outside of the substrate (21). In the recess (24) for containing the optical component for an optical fiber amplifier, an optical component such as a photocoupler is fitted and coupled with the optical fiber. Light such as pumping light is passed through an optical fiber contained in the groove (23) for containing the optical fiber and introduced to an optical component such as a photocoupler.

Abstract: An element for the amplification of a light by stimulated emission of radiation and a method of making the same is described herein.

Abstract: A system for homogenizing a laser pulse emitted by a laser source in order to illuminate a target homogeneously, the system having, between the laser source and the target: a phase plate constituted by a plurality of subpupils capable of generating a plurality of delayed laser beams towards the target, the path difference ?d between two adjacent delayed laser beams being greater than or equal to the length of the temporal coherence Tc of the laser pulse, and focusing device; wherein the subpupils and the focusing device are adjusted so that the delayed laser beams are superimposed on the target in a homogeneous spot.

Abstract: A compact solid state laser that generates multiple wavelengths and multiple beams that are parallel, i.e., bore-sighted relative to each other, is disclosed. Each of the multiple laser beams can be at a different wavelength, pulse energy, pulse length, repetition rate and average power. Each of the laser beams can be turned on or off independently. The laser is comprised of an optically segmented gain section, common laser resonator with common surface segmented cavity mirrors, optically segmented pump laser, and different intra-cavity elements in each laser segment.

Abstract: The invention relates to a laser device (1) for amplifying and/or transporting electromagnetic radiation, comprising a radiation source (2) for generating the electromagnetic radiation and an amplifier (4) for amplifying or a medium for transporting the generated electromagnetic radiation. In order to make available a device (1) for amplifying or transporting electromagnetic radiation that provides a very easy to implement possibility for reducing the influence of non-linear effects, the electromagnetic radiation propagating in the amplifier (4) or medium is largely non-linearly polarized.

Abstract: A waveguide amplifier, disposed on a substrate, composed of sputtered film of chalcogenide glass doped with Erbium is disclosed. The amplifier includes a substrate, a thick film of chalcogenide glass disposed on the substrate, a pumping device, and an optical combining device, wherein the waveguide is operable to amplify the optically combined signal. This type of amplifier has been shown to be compact and cost-effective, in addition to being transparent in the mid-IR range as a result of the low phonon energy of chalcogenide glass.

Abstract: A spatial filter includes a first filter element and a second filter element overlapping with the first filter element. The first filter element includes a first pair of cylindrical lenses separated by a first distance. Each of the first pair of cylindrical lenses has a first focal length. The first filter element also includes a first slit filter positioned between the first pair of cylindrical lenses. The second filter element includes a second pair of cylindrical lenses separated by a second distance. Each of the second pair of cylindrical lenses has a second focal length. The second filter element also includes a second slit filter positioned between the second pair of cylindrical lenses.

Abstract: Laser light emission across a wide bandwidth emission spectrum is enabled in a laser device equipped with solid gain media. The laser device is equipped with: a resonator; a plurality of solid gain media, having fluorescent spectra that at least partially overlap with each other, provided within the resonator; and pumping means, for pumping the plurality of solid gain media. The entire fluorescent spectrum width of the plurality of solid gain media is greater than the fluorescent spectrum width of each solid gain medium.

Abstract: Laser light emission across a wide bandwidth emission spectrum is enabled in a laser amplifier equipped with solid gain media. The laser amplifier is equipped with: a resonator; a plurality of solid gain media, having fluorescent spectra that a least partially overlap with each other, provided within the resonator; and pumping means, for pumping the plurality of solid gain media. The entire fluorescent spectrum width of the plurality of solid gain media is greater than the fluorescent spectrum width of each solid gain medium.

Abstract: A light-emitting device is provided which includes a gain medium having an optically-active phosphosilicate glass, wherein the phosphosilicate glass includes at least one active ion dopant and from about 1 to 30 mol % of phosphorus oxide. The phosphorous oxide may be present in an effective amount for reducing any photodarkening effect and increasing the saturation energy of the system. The active ion dopant may be a rare earth dopant. The light-emitting device may include an optical waveguide, the optical waveguide including the gain medium.

Abstract: A germanate glass composition suitable for use in a fiber amplifier for broadband amplification of optical signals is provided. The glass preferably includes 35-75% GeO2, 0-45% PbO, 5-20% BaO, 5-20% ZnO, and 2-10% R2O (R=Na, Li, K). It is doped with thulium ions (Tm3+) and codoped with holmium ions (Ho3+). The glass composition of results in a remarkably large bandwidth as compared with previous glasses. It is also highly compatible with existing silica optical fibers.

Abstract: An optical element of the present invention exhibits at least one of an upconversion emission characteristic and a light amplifying characteristic when irradiated with an excitation light. The optical element includes a bulk glass that contains titanium oxide as a main component, and the glass further contains a rare earth element. As the rare earth element, at least one element of Er and Yb, or a combination of Yb and Tm preferably is used, for example.

Abstract: The present invention aims to provide a display screen where pixels are addressed by a scanning LASER. The screen performs as a photo-amplifier circuit, producing light output at the region being illuminated by the LASER. This illumination produces electron-hole pairs forming two small currents, one of which subsequently results in a much larger electron or hole current from a specific region of the photo-amplifier. This larger current reaches an emitting region where recombination with other electrons or holes produces light. The duration of the light output is increased up to a frame period or more by increasing the duration of the larger current using various materials having properties that prolong recombination of electrons and holes in a specific device region. In another instance, a feedback effect is utilized by using the incident output light, which may be filtered, replacing the scanning LASER that has left the pixel.

Abstract: There is provided a wide-band optical amplifying device capable of performing amplification over a wideband in infrared range. The wideband optical amplifier is characterized in that optical amplification is realized by optically exciting a glass or a crystal having bismuth as fluorescent center and that the amplification wavelength is 1000 nm to 1600 nm.

Abstract: A method and apparatus is described that use an index-of-refraction profile having a significant central dip in refractive index (or another tailored index profile) within the core of a gain fiber or a gain waveguide on a substrate. The benefits of this central dip (more power with a given mode structure) are apparent when an input beam is akin to that of a Gaussian mode. In some embodiments, the invention provides a fiber or a substrate waveguide having an index profile with a central dip, but wherein the device has no doping. Some embodiments use a central dip surrounded by a higher-index ring in the index of refraction of the core of the fiber, while other embodiments use a trench between an intermediate-index central core portion and the ring, or use a plurality of rings and/or trenches. Some embodiments use an absorber in at least one core ring.

Abstract: The invention relates to a photostructurable body, in particular glass or glass-ceramic, in which the glass is a multicomponent glass and/or the glass-ceramic is a multicomponent glass-ceramic, in each case having a positive change in refractive index ?n as a result of the action of light.

Abstract: In a method of amplifying optical input signals over a wide bandwidth, the optical input signals are applied to an optical waveguide made from a rare-earth-doped amorphous material (e.g., erbium-doped Bi4Ge3O12 material). The optical input signals include optical signals having wavelengths over a range of approximately 125. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over the approximately 125-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end or the range.

Abstract: In a method of amplifying optical input signals over a wide bandwidth, the optical input signals are applied to an optical waveguide made from a rare-earth-doped amorphous material (e.g., erbium-doped SrY4(SiO4)3O material). The optical input signals include optical signals having wavelengths over a range of approximately 125 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over approximately a 125-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end of the range.

Abstract: An optical amplifier comprises a doped fiber core and a cladding layer surrounding the core. The mode field diameter of the fiber is greater than 8 ?m and the refractive index difference between the core and the cladding layer is selected such that the cut-off wavelength at which the fiber becomes single mode lies in the range 1000-1550 nm. This amplifier uses a large made field diameter fiber, which reduces the intensity for a specified output power. This results in reduced filtering of the low frequency components of the signal. The refractive index difference between the core and cladding is selected such that the fiber is multi-mode at 980 nm, which enables bend performance to be improved.

Abstract: A tellurite glass material has a composition of Li2O:TiO2:TeO2, and contains a dopant comprising ions of a rare earth metal. The rare earth ions can be thulium ions, Tm3+, to provide a material offering optical gain at 1470 nm. The properties of the glass make it suitable for the fabrication of high quality optical fibers and planar waveguides, which can in turn be used in optical amplifiers and oscillators. Co-doping the glass with acceptor ions such as holmium ions, Ho3+, improves the population inversion in the rare earth ions and hence enhances the gain.

Abstract: A laser device employs a laser slab having an ionic layer and a nonionic layer, joined through an optical-quality interface. The laser slab has a trapezoidal cross-section in a direction perpendicular to the optical-quality interface. Thermal conductivity away from the ionic layer is enhanced through the thinness of the ionic layer and through the use of a heatsink attached to the ionic layer. Optical power input through the nonionic layer and into the ionic layer is further increased through the use of the trapezoidal cross section.

Abstract: A host material for Tm3+-doping is provided. The host material is a fluorophosphate glass having a non-zero concentration of Tm3+, cation elements that include at least an alkaline earth, phosphorus, and aluminum, and anion elements that include oxygen (O) and fluorine (F). The fluorine(F)/oxygen (O) ratio (F/(F+O)) for the fluorophosphate glass of the embodiments of the present invention can be in the range of about 0.5 to about 0.85. The fluorophosphate glass further can have an alkali metal concentration of 10 mole % or less to improve durability. The Tm-doped fluorophosphate glass can be incorporated into an amplifier or laser utilized in the 14xx nm wavelength region.

Abstract: In a method of amplifying optical input signals over a wide bandwidth, the optical input signals are applied to an optical waveguide made from a rare-earth-doped amorphous material (e.g., erbium-doped yttrium aluminum oxide material). The optical input signals include optical signals having wavelengths over a range of at least 80 nanometers, and, preferably, over a range of at least 160 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over the extended 80-160-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end or the range.

Abstract: In order to improve a laser amplifying system, comprising a solid-state member which has flat sides located opposite one another, is of a plate-like design and comprises a laser-active medium, a laser radiation field passing through the solid-state member, a pumping radiation field pumping the laser-active material, a cooling device which absorbs heat from the solid-state member via a first flat side by means of a fluid cooling medium flowing in it, and a reflector for the laser radiation field arranged on the first flat side, of the generic type in such a manner that the solid-state member may be arranged and aligned in as optimum a manner as possible it is suggested that a support with a stable shape be provided for the solid-state member, this support having the laser radiation field passing through it and being transparent for it, that the solid-state member be supported areally on a support surface of the support with a stable shape with its second flat side and be arranged so as to be defined in its sha

Abstract: In a method of amplifying optical input signals over a wide bandwidth, the optical input signals are applied to an optical waveguide made from a rare-earth-doped amorphous material (e.g., erbium-doped yttrium aluminum oxide material). The optical input signals include optical signals having wavelengths over a range of at least 80 nanometers, and, preferably, over a range of at least 160 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over the extended 80-160-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end or the range.

Abstract: The meters of coiled silica fiber in conventional R-EDFAs is replaced with an ultra-short high-gain waveguides formed of co-doped erbium-ytterbium multi-component glass a few centimeters in length. The compact R-EDA is pumped using non-conventional multi-mode pumps that couple to the waveguide cladding. The multi-component glasses support doping concentrations of the rare-earth ions erbium and ytterbium far in excess of levels believed possible with conventional glasses. These dopant levels in combination with the reflective scheme make a compact R-EDA with sufficient amplification possible.

Abstract: A modified silica glass composition for providing a reduction in the multiphonon quenching for a rare-earth dopant comprising: SiO2 in a host material; a rare-earth dopant; a first SiO2 modifier; and a second SiO2 modifier; such that said first modifier and said second modifier reduce multiphonon quenching of the rare-earth dopant contained therein.

Abstract: A family of tellurite glasses and optical components for telecommunication systems, the glasses consisting essentially of, as calculated in cation percent, 65-97% TeO2, and at least one additional oxide of an element having a valence greater than two and selected from the group consisting of Ta, Nb, W, Ti, La, Zr, Hf, Y, Gd, Lu, Sc, Al and Ga, that may contain a lanthanide oxide as a dopant, in particular erbium oxide, and that, when so doped, is characterized by a fluorescent emission spectrum having a relatively broad FWHM value.

Abstract: An optical amplifying glass having Er doped in an amount of from 0.01 to 10% as represented by mass percentage to a matrix glass comprising, by mol %, BiO2: 20 to 80, B2O3+SiO2: 5 to 75, Ga2O3+WO3+TeO2: 0.1 to 35, Al2O3≦10, GeO2≦30, TiO2≦30, and SnO2≦30, and containing no CeO2.

Abstract: A glass-ceramic which is substantially and desirably totally transparent, and which contains a predominant crystal phase of forsterite. The glass-ceramic is formed from precursor glasses having the following compositions, in weight percent on an oxide basis: SiO2 30-60; Al2O3 10-25; MgO 13-30; K2O 8-20; TiO2 0-10; and GeO2 0-25. The glass-ceramic may be doped with up to 1 wt. % chromium oxide to impart optical activity thereto.

Abstract: An optical amplifying unit includes an input for the input optical signals and an output for the output of the optical signals. A single-mode active fiber codoped with Er and Yb is optically connected to the input and the output and adapted to amplify the optical signals. A first pump source generates a first pump radiation including an excitation wavelength for Er, and a second pump source for generates a second pump radiation including an excitation wavelength for Yb. A first optical coupler optically couples the first pump radiation into the core of the active fiber in a co-propagating direction with respect to signal direction, and a second optical coupler optically couples the second pump radiation into the core of the active fiber in a counter-propagating direction with respect to signal direction.

Abstract: An optical amplifier glass comprising a matrix glass containing Bi2O3 and at least one of Al2O3 and Ga2O3, and Er doped to the matrix glass, wherein from 0.01 to 10% by mass percentage of Er is doped to the matrix glass which has a total content of Al2O3 and Ga2O3 of at least 0.1 mol %, a content of Bi2O3 of at least 20 mol %, a refractive index of at least 1.8 at a wavelength of 1.55 &mgr;m, a glass transition temperature of at least 360° C. and an optical basicity of at most 0.49.

Abstract: The invention concerns elemental silicon emission devices. Devices according to the invention use elemental silicon nanoparticles as a material from which stimulated emissions are produced. Silicon nanoparticles efficiently produce emissions and act as a gain medium in response to excitation. The silicon nanoparticles of the invention, being dimensioned on an order of magnitude of one nanometer and having about 1 part per thousand or less larger than 1 nm, are an efficient emission source and forms the basis for many useful devices.

Abstract: A Tm-doped germanate glass composition comprises GeO2 having a concentration of at least 20 mole percent, Tm2O3 having a concentration of about 0.001 mole percent to about 2 mole percent, and Ga2O3, having a concentration of about 2 mole percent to about 40 mole percent. The composition can further include an alkaline earth metal compound selected from the group consisting of MgO, CaO, SrO, BaO, BaF2, MgF2, CaF2, SrF2, BaCl2, MgCl2, CaCl2, SrCl2, BaBr2, MgBr2, CaBr2, SrBr2, and combinations thereof, and having a non-zero concentration of less than about 40 mole percent. The composition can further include an alkali metal compound selected from the group consisting of Li2O, Na2O, K2O, Rb2O, Cs2O, Li2F2, Na2F2, K2F2, Rb2F2, Cs2F2, Li2Cl2, Na2Cl2, K2Cl2, Rb2Cl2, Cs2Cl2, Li2Br2, Na2Br2, K2Br2, Rb2Br2, Cs2Br2 and combinations thereof, and having a non-zero concentration of less than about 20 mole percent.

Abstract: The specification describes rare earth doped fiber amplifier devices for operation in the extended L-band, i.e. at wavelengths from 1565 nm to above 1610 nm. High efficiency and flat gain spectra are obtained using a high silica based fiber codoped with Er, Al, Ge, and P and an NA of at least 0.15.

Abstract: An optical gain fiber of the present invention is doped with rare earth ions for improving a gain efficiency of a certain transition of the rare earth ions by inhibiting an undesirable amplified spontaneous emission. The optical gain fiber for amplifying an optical signal, includes a core doped with a first rare-earth ion in a portion thereof for amplifying the optical signal, and a clad doped with a second rare earth ion for absorbing an undesirable amplified spontaneous emission (ASE) emitted from the first rare earth ion, wherein the portion of the core and the potion of the clad are separated by the remaining portions of the core and the clad.

Abstract: An optical fiber is for optical amplification used for 1.58 &mgr;m band signal light amplification, at least a core region thereof being doped with Er. At least a part of the core region is made of silica glass co-doped with Ge and Al together with Er. The Er average atomic concentration in the core region is from 1500 wt-ppm to 3000 wt-ppm inclusive, and cutoff wavelength is from 0.8 &mgr;m to 1.1 &mgr;m inclusive.

Abstract: The object of this invention is to improve SNR in the Raman amplification. An optical fiber (10) consists of a dispersion shift fiber in which a zero dispersion wavelength is shifted to the 1.55 &mgr;m band, and an optical fiber (12) consists of a single mode optical fiber having the effective core area of 100 &mgr;m2 which is larger than that of the optical fiber (10). An optical coupler 14 is disposed at the optical signal emission end of the optical fiber (12). A laser diode (16) outputs the laser light of 1455 nm as a Raman pumping light source. The output light from the laser diode (16) is introduced into the optical fiber (12) from the back, namely in the opposite direction to that of the optical signal propagation. The ratio of the Raman gain coefficient of the optical fiber (12) to that of the optical fiber (11) should be 1/1.08 or less, preferably 1/1.1 or less.

Abstract: A borosilicate glass composition comprises SiO2 having a concentration of about 40 mole percent to about 60 mole percent, B2O3 having a concentration of about 10 mole percent to about 30 mole percent, and an alkaline earth and/or alkali compound having a concentration of 10 mole percent to about 40 mole percent. An optical fiber amplification device comprises a borosilicate glass material cladding. The core comprises a germanate glass material doped with Tm3+. The germanate glass material has a first surface configured to receive an optical signal having a wavelength of from about 1400 nm to about 1540 nm and a second surface configured to output an amplified optical signal. In this manner, low cost fiber amplifiers in the 1450-1530 nm wavelength region (corresponding to the S-band) can be achieved.

Abstract: Many longitudinally pumped miniature lasers (single-frequency Nd:YAG microchip lasers and Q-switched microchip lasers) are sufficiently short that only a small fraction of the incident pump light is absorbed as it passes through the gain medium. The efficiency of such a laser is improved when the output face of the laser is coated to reflect the pump light, thereby allowing double-pass absorption of the light within the gain medium. The total absorption may still be small, however. Additionally, the divergence of typical pump sources (diode lasers or optical fibers) is large enough that there is often poor overlap between the reflected pump light and the oscillating mode, and the efficiency of the device is not significantly enhanced. If the output face of the miniature laser is coated to be highly transmitting to the pump radiation, the transmitted pump light can be collected with a lens and focused in to an amplifying medium (Nd:YVO4).

Abstract: An optical amplifier includes a chalcogenide glass optical waveguide having optical input and output ports, coupled to the chalcogenide glass optical waveguide, a pump optical waveguide, and a wavelength-tunable pump laser. The pump optical waveguide couples the wavelength-tunable pump laser to the chalcogenide glass optical waveguide.

Abstract: In a method of amplifying optical input signals over a wide bandwidth, the optical input signals are applied to an optical waveguide made from a rare-earth-doped amorphous material (e.g., erbium-doped yttrium aluminum oxide material). The optical input signals include optical signals having wavelengths over a range of at least 80 nanometers, and, preferably, over a range of at least 160 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals. The optical gain causes the optical signals to be amplified within the waveguide to provide amplified optical signals over the extended 80-160-nanometer range, including, in particular, optical signals having wavelengths at one end of the range and optical signals having wavelengths at a second end or the range.

Abstract: An optical amplifier of the present invention is implemented by using a low phonon energy glass doped with praseodymium ions (Pr3+), whereby a wavelength of 1.6 &mgr;m band can be used for an optical transmission. The optical amplifier for amplifying an optical signal includes a low phonon energy optical medium doped with praseodymium ions (Pr3+) for utilizing as a gain medium to the optical signal, and a pumping means for pumping the low phonon energy optical medium, thereby to obtain an amplified optical signal.

Abstract: An optical amplifier comprises a trivalent thulium-doped optical fiber; a first pump light emitting device optically coupled to the fiber for generating a primary pump source at a first wavelength, and a second pump light emitting device optically coupled to the fiber for generating a secondary pump source at a second wavelength. In a preferred aspect of the present invention, the amplifier also includes a third (auxiliary) pump light emitting device optically coupled to the fiber for generating a third pump source at a third wavelength. Each of the amplification signals comprise at least one pre-selected wavelength. The first amplification signal has a wavelength pre-selected to provide a reduced noise figure for the amplifier. The second amplification signal has a wavelength pre-selected to increase the optical efficiency of the amplifier. The third amplification signal can have a wavelength pre-selected to populate the 3F4 energy level of the fiber, and to minimize depletion of the 3H6 ground state.

Abstract: In a method of amplifying optical input signals over a wide bandwidth, the optical input signals are applied to an optical waveguide made from a rare-earth-doped amorphous yttrium aluminum oxide material (e.g., erbium-doped yttrium aluminum oxide material). The optical input signals include optical signals having wavelengths shorter than 1,520 nanometers and optical signals having wavelengths longer than 1,610 nanometers. Preferably, the wavelengths range from as short as approximately 1,480 nanometers to as long as approximately 1,650 nanometers. Pump light is applied to the optical waveguide to cause the waveguide to provide optical gain to the optical input signals.

Abstract: An active optical amplifier in which a unitary optical amplifier constructed from a unitary optically transparent chip that has been doped so as to be optically active, amplifies incoming signal photons when excited by a pump laser of sufficient energy. The unitary optical amplifier receives input photons and pump laser energy and provides output photons that have the same spatial orientation and phase as the corresponding input photons. A laser direction and ranging (LADAR) may be constructed from the active optical amplifier by further including first imaging optics to focus the input photons onto the surface of the unitary optical amplifier and second imaging optics to focus the output photons from the active unitary optical amplifier onto a focal plane image sensor array. The electronic signals from the focal plane image sensor array may then be displayed on a conventional display.

Abstract: The present invention relates to an in-line optical amplifier that can be coupled to optical fiber, wherein the amplifying medium has a substantially larger mode field than the optical fiber to which it is coupled. The present invention has realized a design to utilize a very high power pump launching a multimoded signal having approximately 1 W of pump power into a block of erbium doped glass having a mode field diameter orders of magnitude larger than the mode field diameter of erbium doped fiber. This invention provides a relatively inexpensive optical amplifier that is compatible for use in an optical fiber telecommunications system or for other uses. Advantageously, this invention provides a device that does not require unwieldy lengths of erbium doped fiber to form an amplifier. By using a block of glass having a rare earth therein, packaging, temperature stabilizing and temperature tuning of the amplifier also become practicable.

Abstract: The invention relates to a family of erbium-doped fluorophosphate glasses for use in optical signal amplification and which are doped, for 100 parts by weight constituted by: P2O5 15-40 MgF2 0-10 Al2O3  0-5 CaF2 0-25 MgO  0-9 SrF2 0-25 CaO  0-9 BaF2 0-20 SrO  0-9 KHF2 0-2 BaO  0-45 K2TiF6 0-2 AlF3  5-25 with up to 10 parts by weight of erbium oxide. The glasses according to the present invention exhibit a high gain and very flat spectrum over the 1550 nm bandwidth. These glass compositions are particularly well suited for use in fiber or planar optical amplification in WDM and similar applications.

Abstract: An integrated photonic apparatus that includes a glass substrate having a major surface, wherein the glass substrate includes a plurality of regions, each region having a different index of refraction, including a first region having a first index of refraction and a second region having a second index of refraction lower than the first index of refraction, and a first waveguide formed along the major surface of the substrate, wherein the first waveguide has a higher index of refraction than an intrinsic index of refraction of adjacent portions of the substrate, and wherein the first waveguide passes through the first region and through the second region of the glass substrate.