[Object] To provide a single-crystal fiber production equipment and a single-crystal fiber production method that do not at all require high precision control necessary for a conventional single-crystal production equipment, can very easily maintain a stable steady state for a long time, and can stably produce a long single crystal fiber having a length of several hundreds of meters or more.

[Solution] The single-crystal fiber production equipment is used to produce a single crystal fiber by irradiating an upper surface of a raw material rod with a laser beam within a chamber to form a melt, immersing a seed single crystal in the melt, and pulling the seed single crystal upward. The single-crystal fiber production equipment includes: a laser light source that emits the laser beam as a collimated beam; a pulling device configured to be upward and downward movable in a vertical direction with the seed single crystal held thereby; and a flat reflector that reflects the laser beam such that the reflected laser beam is incident vertically on the upper surface of the raw material rod. The upper surface of the raw material rod is irradiated with the laser beam such that the melt has a donut-shaped temperature distribution.

Process for fabricating a thin single-crystalline layer n, including steps of: a) providing a support substrate n, b) placing a seed sample n, c) depositing a thin layer n so as to form an initial interface region n including a proportion of seed sample n and a proportion of thin layer n, the proportion of seed sample n decreasing from the first peripheral part n towards the second peripheral part n, e) providing an energy input to the initial interface region n contiguous to the first peripheral part n so as to liquefy a portion n of the thin layer and form a solid/liquid interface region n, and f) gradually moving the energy input away from the seed sample n so as to solidify the portion n so as to gradually move the solid/liquid interface region n.

A single crystal manufacturing apparatus to grow a single crystal upward from a seed crystal, the apparatus including an insulated space thermally insulated from a space outside the single crystal manufacturing apparatus, an induction heating coil placed outside the insulated space, a thermal insulation plate that divides the insulated space into a first space including a crystal growth region to grow the single crystal and a second space above the first space and includes a hole above the crystal growth region, a heating element that is placed in the second space and generates heat by induction heating using the induction heating coil to heat the inside of the insulated space, and a support shaft to vertically movably support the seed crystal from below.

One or more embodiments relate to a method for controlling fiber growth and fiber diameter in a laser heated pedestal growth (LHPG) system so as to provide long, continuous single-crystal optical fibers of uniform diameter. The method generally provides three independent parameter feedback controls to control the molten zone height, laser power, and fiber drawing rates simultaneously in order to reduce the mismatch between instantaneous diameter changes and current diameter. The method permits the growth of fibers with non-uniform diameters along the fiber's length. The method also provides the capability to stop the LHPG system, remove the exhausted pedestal feedstock with a second pedestal feedstock, and restart the LHPG system to provide a continuous fiber.

[Object] To provide a single-crystal fiber production equipment and a single-crystal fiber production method that do not at all require high precision control necessary for a conventional single-crystal production equipment, can very easily maintain a stable steady state for a long time, and can stably produce a long single crystal fiber having a length of several hundreds of meters or more. [Solution] The single-crystal fiber production equipment is used to produce a single crystal fiber by irradiating an upper surface of a raw material rod with a laser beam within a chamber to form a melt, immersing a seed single crystal in the melt, and pulling the seed single crystal upward. The single-crystal fiber production equipment includes: a laser light source that emits the laser beam as a collimated beam; a pulling device configured to be upward and downward movable in a vertical direction with the seed single crystal held thereby; and a flat reflector that reflects the laser beam such that the reflected laser beam is incident vertically on the upper surface of the raw material rod. The upper surface of the raw material rod is irradiated with the laser beam such that the melt has a donut-shaped temperature distribution.

A single crystal manufacturing apparatus to grow a single crystal upward from a seed crystal, the apparatus including an insulated space thermally insulated from a space outside the single crystal manufacturing apparatus, an induction heating coil placed outside the insulated space, a thermal insulation plate that divides the insulated space into a first space including a crystal growth region to grow the single crystal and a second space above the first space and includes a hole above the crystal growth region, a heating element that is placed in the second space and generates heat by induction heating using the induction heating coil to heat the inside of the insulated space, and a support shaft to vertically movably support the seed crystal from below.

In general, the systems and methods described in this application relate to laser-induced nucleation in continuous flow. A method of laser-induced nucleation in continuous flow includes injecting a saturated solution, undersaturated solution, or supersaturated solution through an inlet of a device. The method can include converting the saturated solution or undersaturated solution into supersaturated solution by changing a temperature of the saturated solution or undersaturated solution. The method can include passing one or more laser pulses through the supersaturated solution within the device. The method can include flowing the saturated solution, undersaturated solution, or the supersaturated solution through an outlet of the device.

In general, the systems and methods described in this application relate to laser-induced nucleation in continuous flow. A method of laser-induced nucleation in continuous flow includes injecting a saturated solution, undersaturated solution, or supersaturated solution through an inlet of a device. The method can include converting the saturated solution or undersaturated solution into supersaturated solution by changing a temperature of the saturated solution or undersaturated solution. The method can include passing one or more laser pulses through the supersaturated solution within the device. The method can include flowing the saturated solution, undersaturated solution, or the supersaturated solution through an outlet of the device.

A laser heated pedestal growth system includes two lasers having output beams that are combined with a beam combiner to produce a single beam. A growth chamber that includes a final focusing mirror for receiving and focusing the single beam of the lasers onto a tip of a feed material to create a molten zone in a focal region. A feed transport mechanism is adapted for transporting a feed material through the growth chamber and into the molten zone. An opposing seed transport mechanism is adapted for withdrawing a seed material from the growth chamber. An imaging system is adapted for capturing an image of the molten zone within the growth chamber. A controller in communication with the feed transport mechanism, the seed transport mechanism, one of the two lasers, and the imagining system is adapted to control and stabilize a fiber growth process by controlling the feed transport mechanism, the seed transport mechanism, and the power of the combined laser beam.

Sol-gel methods, apparatus and compositions for cladding optical fiber cores provide optical fibers, including single crystal optical fiber cores with polycrystalline cladding, having improved performance in a variety of applications, such as fiber lasers.