An example system and corresponding method can include a combustion chamber of jet engine, a radio-frequency power source, and a resonator. The combustion chamber can include a liner defining a combustion zone, and include a fuel inlet configured to introduce fuel into the combustion zone. The resonator can have a resonant wavelength and include: a first conductor, a second conductor, a dielectric, and an electrode coupled to the first conductor. The resonator can be configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter () of the resonant wavelength, the resonator provides a plasma corona in the combustion zone. The controller can be configured to cause the radio-frequency power source to excite the resonator with the signal so as to provide the plasma corona.

Example implementations relate to electromagnetic wave modification of fuel in a power-generation turbine. An example implementation includes a power-generation turbine. The power-generation turbine includes a combustion chamber, a radio-frequency power source, and a fuel conduit configured to provide a fuel to the combustion chamber. In addition, the power-generation turbine includes a resonator configured to electromagnetically couple to the radio-frequency power source and having a resonant wavelength. The resonator includes a first conductor, a second conductor, and a dielectric between the first conductor and the second conductor. The resonator is configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter () of the resonant wavelength, the resonator radiates electromagnetic waves usable to modify (i) the fuel within the fuel conduit or (ii) a fuel mixture, which includes the fuel, within the combustion chamber.

The adapter shaping an electromagnetic field heats toroidal plasma discharge. It is intended for use in plasma torches dedicated for excitation/ionization sources in spectrometers. The adapter includes at least two electromagnetic field shaping elements, which are stretched between the bushing of the upper microwave connection and the bushing of the lower microwave connection. An element shaping electromagnetic field is positioned to the surface pitch of the bushings at an angle ranging from 0 to 90 degrees.

A configuration is provided in which two high-frequency power transmission antennas 111, 121 formed on two microstrip lines 101, 102, respectively, are disposed to face each other with an insulating sheet 103 interposed between the two high-frequency power, and the high-frequency power transmission antennas 111, 121 are formed on the two microstrip lines 101, 102, respectively, to realize transmission of high-frequency power, to make it possible to reduce the size of a DC block as compared with a conventional DC block using a coaxial line shape or a waveguide shape, and make it possible to highly efficiently transmit only high-frequency power while cutting off high-voltage direct-current power by the insulating sheet 103.

A plasma-generation system is provided that includes a variable-frequency microwave generator configured to generate microwave power and a plasma applicator configured to use the microwave power from the microwave generator to (i) ignite a process gas therein for initiating a plasma in a plasma ignition process and (ii) maintain the plasma in a steady state process. The system also includes a coarse tuner connected between the microwave generator and the plasma applicator. At least one physical parameter of the coarse tuner is adapted to be set to achieve coarse impedance matching between the microwave generator and the plasma generated during both the plasma ignition process and the steady state process. A load impedance of the plasma generated during the plasma ignition process and the steady state process is adapted to vary. The microwave generator is configured to tune an operating frequency at the set physical parameter of the coarse tuner.

The adapter shaping an electromagnetic field heats toroidal plasma discharge. It is intended for use in plasma torches dedicated for excitation/ionization sources in spectrometers. The adapter includes at least two electromagnetic field shaping elements, which are stretched between the bushing of the upper microwave connection and the bushing of the lower microwave connection. An element shaping electromagnetic field is positioned to the surface pitch of the bushings at an angle ranging from 0 to 90 degrees.

The disclosure provides a plasma source and an excitation system for excitation of a plasma, and an optical monitoring system. In one embodiment the plasma source includes: (1) a coaxial resonant cavity body having an inner length, and including a first end, a second end, an inner electrode and an outer electrode, (2) a radio frequency signal interface electrically coupled to the inner and outer electrodes at a fixed position along the inner length and configured to provide a radio frequency signal to the coaxial resonant cavity body, (3) a window positioned at the first end of the coaxial resonant cavity body, and (4) a mounting flange positioned proximate the window at the first end of the coaxial resonant cavity body and defining a plasma cavity, wherein the window forms one side of the plasma cavity and isolates the coaxial resonant cavity body from plasma in the plasma cavity.

An apparatus for depositing a coating on a substrate at atmospheric pressure comprises (a) a plasma torch comprising a microwave source coupled to an antenna disposed within a chamber having an open end, the chamber comprising a gas inlet for flow of a gas over the antenna to generate a plasma jet; (b) a substrate positioned outside the open end of the chamber a predetermined distance away from a tip of the antenna; and (c) a target material to be coated on the substrate disposed at the tip of the antenna.

A plasma antenna assembly may include a plasma antenna element, a plasma density sensor operably coupled to the plasma antenna element to measure plasma density during ionization of the plasma antenna element, a driver circuit operably coupled to the plasma antenna element to selectively provide pulsed current to the plasma antenna element for ionization of plasma in the plasma antenna element, and a controller operably coupled to the driver circuit and the plasma density sensor to provide control of the plasma density of the plasma antenna element.

A plasma reactor for processing a workpiece includes a chamber having a dielectric window, a workpiece support to hold a workpiece in the chamber, a rotary coupling comprising a stationary stage configured to be coupled to a microwave source and a rotatable stage having an axis of rotation, a microwave antenna and overlying the dielectric window of the chamber, a rotary actuator to rotate the microwave antenna, and a process gas distributor including a gas distribution ring surrounding the workpiece support. The microwave antenna includes at least one conduit coupled to the rotary stage. The gas distribution ring including a cylindrical chamber liner separating a circular conduit from the chamber and a plurality of apertures extending radially through the liner to connect the conduit to the chamber.