Masers and microwave amplifiers that can function in the continuous-wave mode at room temperature are provided. The maser system can include a diamond gain medium having nitrogen-vacancy centers, and a resonator can be disposed around the gain medium. The resonator can be disposed in a cavity box, and radiation (e.g., visible light) can be provided to the gain medium to cause emission of microwave radiation.

A slab laser and its method of use for high power applications including the manufacture of semiconductors and deposition of diamond and/or diamond-like-carbon layers, among other materials. A lamp driven slab design with a face-to-face beam propagation scheme and an end reflection that redirects the amplified radiation back out the same input surface is utilized. A side-to-side amplifier configuration permitting very high average and peak powers having scalability is also disclosed. Cavity filters adjacent to pump lamps convert the normally unusable UV portion of the pump lamp spectrum into light in the absorption band of the slab laser, thereby increasing the overall pump efficiency. The angle of the end reflecting surface is changed to cause the exit beam to be at a different angle than the inlet beam, thereby eliminating the costly need to separate the beams external to the laser with the subsequent loss of power.

An object is to provide an optical device capable of relaxing a manufacturing condition for an optical waveguide used in the optical device. An optical device 500 is provided with an optical waveguide 200 including a core and a cladding optically joined together, and a temperature controller 600 that controls temperature of the optical waveguide, wherein the optical waveguide includes the core and the cladding formed such that a normalized frequency specified for light propagating through the optical waveguide changes across a cutoff frequency of a guided mode determined from a structure of the optical waveguide in a temperature range in which a refractive index of the core is higher than a refractive index of the clad. The temperature controller controls the temperature of the optical waveguide over a temperature range across temperature at which the normalized frequency equals to the cutoff frequency.

The present invention provides a blue laser transmitter operating at the H-beta Fraunhofer line at 486.13 nm wavelength. The subject blue laser is based on pulsed lasing action in thulium doped into lutetium sesquioxide (Tm:Lu.sub.2O.sub.3). The laser wavelength is restricted by volume Bragg grating to the vicinity of 1944 nm wavelength. The laser is operated with a q-switch to generate high-energy pulses within the nanosecond regime. The output at the 1944 nm wavelength is then frequency quadrupled in a single pass through non-linear crystals to a wavelength near the center of the H-beta Fraunhofer line. The operation at the 1944 nm wavelength in Tm:Lu.sub.2O.sub.3 is very efficient because this wavelength is located on a shoulder of a substantially broad emission peak at 1945 nm. In addition, at the 1944 nm wavelength, Tm:Lu.sub.2O.sub.3 has only a modest saturation fluence of about 15 J/cm.sup.2, which allows for efficient energy extraction.

A photonic integrated circuit includes a pumping laser diode that is designed to emit pumping radiation The photonic integrated circuit furthermore includes a gain medium which is suitable for absorbing the pumping radiation and emitting laser radiation and a waveguide which is suitable for feeding the pumping radiation to the gain medium The photonic integrated circuit furthermore includes a first and a second resonator mirror of which one is arranged in a light path between the pumping laser diode and the gain medium and another is arranged on a side of the gain medium which faces away from the pumping laser diode An optical resonator is formed between the first and the second resonator mirror