Abstract: A fiber laser apparatus includes: a short-length type fiber to which an active element is added and that has a length of 300 mm or less: a ferrule attached to an end of the fiber; and a housing that accommodates the fiber and supports the fiber with the ferrule. Each of the housing and the ferrule is composed of a material having a first thermal expansion coefficient that is equal to or have a predetermined difference from a second thermal expansion coefficient of a raw material of the fiber. The predetermined difference between the first and second thermal expansion coefficients is within ?8.6×10?6 to 11.4×10?6/K.

Abstract: An ultraviolet laser apparatus includes: a semiconductor laser that emits an excitation laser light; a fiber laser medium to which the excitation laser light enters from the semiconductor laser and that causes laser oscillation; and an external resonator that: converts a wavelength of a laser light oscillated in the fiber laser medium, and outputs an ultraviolet region continuous wave of at least 0.1W.

Abstract: A fiber laser apparatus includes: a short-length type fiber to which an active element is added and that has a length of 300 mm or less: a ferrule attached to an end of the fiber; and a housing that accommodates the fiber and supports the fiber with the ferrule. Each of the housing and the ferrule is composed of a material having a first thermal expansion coefficient that is equal to or have a predetermined difference from a second thermal expansion coefficient of a raw material of the fiber. The predetermined difference between the first and second thermal expansion coefficients is within ?8.6×10?6 to 11.4×10?6/K.

Abstract: A laser apparatus includes: a laser oscillator that includes a mirror and emits a laser beam; and an external resonator that includes a nonlinear optical crystal that functions as a phase conjugate mirror. The phase conjugate mirror reflects the laser beam and produces a phase conjugate wave that reaches the mirror of the laser oscillator, and the mirror of the laser oscillator and the phase conjugate mirror cause laser oscillation such that a wavelength and a phase of the laser beam oscillated by the laser oscillation are automatically fixed.

Abstract: Provided is a particulate phosphor including a single crystal having a composition represented by a compositional formula (Y1-x-y-zLuxGdyCez)3+aAl5?aO12 (0?x?0.9994, 0?y?0.0669, 0.001?z?0.004, ?0.016?a?0.315) and a particle diameter (D50) of not less than 20 ?m. Also provided is a light-emitting device including a phosphor-including member that includes the phosphor and a sealing member including a transparent inorganic material sealing the phosphor or a binder including an inorganic material binding particles of the phosphor, and a light-emitting element that emits a blue light for exciting the phosphor.

Abstract: A light emitting device includes a laser diode that emits a blue light, and a wavelength conversion part that absorbs a part of light emitted from the laser diode and converts a wavelength thereof. The wavelength conversion part includes a YAG-based single crystal phosphor. Irradiance of light emitted from the laser diode and irradiated on the wavelength conversion part is not less than 80 W/mm2.

Abstract: A phosphor-containing member includes a transparent member, and a plurality of granular single crystal phosphors dispersed in the transparent member. Each of the plurality of granular single crystal phosphors includes a YAG crystal as a mother crystal. The plurality of granular single crystal phosphors are prepared by crushing the YAG crystal. The YAG crystal has a composition represented by a formula of Y3-x-yGdxCeyAl5O12-w (0.03?x?0.2, 0.003?y?0.2, ?0.2?w?0.2). Reduction of fluorescence intensity of the phosphors is less than 3% when an excitation light wavelength is 460 nm and a temperature is increased from 25° C. to 100° C.

Abstract: As one of purposes, the present invention provides: a single-crystal phosphor which can exhibit excellent properties under high-temperature conditions; and a light-emitting device in which the phosphor is used. As one embodiment, a single-crystal phosphor is provided, which has a chemical composition represented by the compositional formula: Y1-x-y-zLuxGdyCez)3+aAl5-aO12(0?x?0.9994, 0?y?0.0669, 0.0002?z?0.0067,?0.016?a?0.315).

Abstract: A light emitting device includes a laser diode that emits a blue light, and a wavelength conversion part that absorbs a part of light emitted from the laser diode and converts a wavelength thereof. The wavelength conversion part includes a YAG-based single crystal phosphor. Irradiance of light emitted from the laser diode and irradiated on the wavelength conversion part is not less than 80 W/mm2.

Abstract: Provided is a method for growing a ?-Ga2O3-based single crystal, whereby it becomes possible to grow a ?-Ga2O3-based single crystal having a small variation in crystal structure and also having a high quality in the direction of a b axis. In one embodiment, a method for growing a ?-Ga2O3-based single crystal includes growing a plate-shaped Sn doped ?-Ga2O3-based single crystal in the direction of the b axis using a seed crystal.

Abstract: According to one embodiment of the present invention, the light emitting device includes an LED element, a side wall which surrounds the LED element, a phosphor layer which is fixed to the side wall with an adhesive layer therebetween, and is positioned above the LED element, and a metal pad as a heat dissipating member. The side wall includes an insulating base which surrounds the LED element and a metal layer which is formed on a side surface at the LED element side of the base, and is in contact with the metal pad and the adhesive layer. The adhesive layer includes a resin layer that includes a resin containing particles which have higher thermal conductivity than the resin or a layer that includes solder.

Abstract: A ?-Ga2O3-based single-crystal substrate includes a ?-Ga2O3-based single crystal, and a principal surface being a plane parallel to a b-axis of the ?-Ga2O3-based single crystal. A maximum value of ?? on an arbitrary straight line on the principal surface that passes through a center of the principal surface is not more than 0.7264. The ?? is a difference between a maximum value and a minimum value of values obtained by subtracting ?a from ?s at each of measurement positions, where ?s represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and ?a represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the ?s and the measurement positions thereof.

Abstract: Provided are: a method for producing a ?-Ga2O3 substrate of which changes in donor concentration in a reducing atmosphere or an inert gas atmosphere are suppressed; and a method for producing a crystal laminate structure that can epitaxially grow a high-quality crystal film having low variability of quality in a reducing atmosphere or an inert gas atmosphere. The method for producing a ?-Ga2O3 substrate includes a step for cutting out a ?-Ga2O3 substrate from a ?-Ga2O3 crystal containing a group IV element; annealing processing in an atmosphere containing a reducing atmosphere and/or an inert gas atmosphere is performed on the ?-Ga2O3 crystal before cutting out the ?-Ga2O3 substrate, or on the cut-out ?-Ga2O3 substrate.

Abstract: A method for growing a ?-Ga2O3-based single crystal, can provide a plate-shaped ?-Ga2O3-based single crystal having high crystal quality. In one embodiment, a method for growing a ?-Ga2O3-based single crystal employing an EFG method is provided, the method including: bringing a plate-shaped seed crystal into contact with a Ga2O3-based melt, wherein the plate-shaped seed crystal includes a ?-Ga2O3-based single crystal having a defect density of not more than 5×105 /cm2 in the whole region; and pulling up the seed crystal to grow a ?-Ga2O3-based single crystal.

Abstract: Provided is one embodiment which is a method for growing a ?-Ga2O3-based single crystal which uses the EFG method and includes raising a Ga2O3 melt inside a crucible up to a die opening via a die slit such that a seed crystal is contacted with the Ga2O3-based melt in the opening of the die with a horizontal position of the seed crystal shifted in a width direction (W) from a center in the width direction (W) of the die, and pulling up the seed crystal contacting the Ga2O3-based melt so as to grown a ?-Ga2O3 single crystal.

Abstract: Provided is one embodiment which is a method for growing a ?-Ga2O3-based single crystal including contacting a flat plate-shaped seed crystal with a Ga2O3-based melt, and pulling up the seed crystal such that a flat plate-shaped ?-Ga2O3-based single crystal having a principal surface which intersects a surface is grown without inheriting a crystal information of a vaporized material of the Ga2O3-based melt adhered to the principal surface of the seed crystal, wherein when growing the ?-Ga2O3-based single crystal, a shoulder of the ?-Ga2O3-based single crystal is widened in a thickness direction (t) thereof.

Abstract: A method for growing a ?-Ga2O3-based single crystal, can provide a plate-shaped ?-Ga2O3-based single crystal having high crystal quality. In one embodiment, a method for growing a ?-Ga2O3-based single crystal employing an EFG method is provided, the method including: bringing a plate-shaped seed crystal into contact with a Ga2O3-based melt, wherein the plate-shaped seed crystal includes a ?-Ga2O3-based single crystal having a defect density of not more than 5×105 /cm2 in the whole region; and pulling up the seed crystal to grow a ?-Ga2O3-based single crystal.

Abstract: According to one embodiment of the present invention, the light emitting device includes an LED element, a side wall which surrounds the LED element, a phosphor layer which is fixed to the side wall with an adhesive layer therebetween, and is positioned above the LED element, and a metal pad as a heat dissipating member. The side wall includes an insulating base which surrounds the LED element and a metal layer which is formed on a side surface at the LED element side of the base, and is in contact with the metal pad and the adhesive layer. The adhesive layer includes a resin layer that includes a resin containing particles which have higher thermal conductivity than the resin or a layer that includes solder.

Abstract: A ?-Ga2O3-based single-crystal substrate includes a ?-Ga2O3-based single crystal, and a principal surface being a plane parallel to a b-axis of the ?-Ga2O3-based single crystal. A maximum value of ?? on an arbitrary straight line on the principal surface that passes through a center of the principal surface is not more than 0.7264. The ?? is a difference between a maximum value and a minimum value of values obtained by subtracting ?a from ?s at each of measurement positions, where ?s represents an angle defined by an X-ray incident direction and the principal surface at a peak position of an X-ray rocking curve on the straight line and ?a represents an angle on an approximated straight line obtained by using least-squares method to linearly approximate a curve representing a relationship between the ?s and the measurement positions thereof.

Abstract: Provided is a gallium oxide substrate which has less linear pits. Obtained is a gallium oxide substrate wherein the average density of linear pits in a single crystal surface is 1,000 pits/cm2 or less.