A device 1 for generating a controlled ionic flow I is described. The device 1 is portable and comprises an ionization chamber 6, at least one inlet member 2 and at least one ion outlet member 3. The ionization chamber 6 is suitable to be kept at a vacuum pressure, and configured to ionize gaseous particles contained therein. The at least one inlet member 2 is configured to inhibit or allow and/or adjust an inlet in the ionization chamber of a gaseous flow Fi of said gaseous particles. In addition, the at least one inlet member 2 comprises a gaseous flow adjusting interface 22, having a plurality of nano-holes 20, of sub-micrometric dimensions, suitable to be opened or closed, in a controlled manner, to inhibit or allow a respective plurality of gas micro-flows through the at least one inlet member 2.

The present invention discloses a positive and negative ion source based on radio-frequency inductively coupled discharge, comprising a tube, a middle portion of which is communicated with an intake pipe; discharge coils electrically connected to a matched network and a radio-frequency power supply successively are wound on the tube; one end of the tube is connected to a first cover plate in a sealed manner, and the first cover plate is connected with a positive ion extraction gate via an insulating medium; the positive ion extraction gate is electrically connected to a negative pole of a DC power supply; the other end of the tube is connected to a second cover plate in a sealed manner, the second cover plate is connected to a third cover plate in a sealed manner via a sidewall, and the third cover plate is connected with a negative ion extraction gate via an insulating medium; and the negative ion extraction gate is electrically connected to a positive pole of the DC power supply. In the present invention, the positive ions and the electrons and negative ions can be extracted simultaneously, and the problems of contamination of the ion source by particles sputtered from the backplane and overheating of the backplane are thus solved.

The present invention discloses a positive and negative ion source based on radio-frequency inductively coupled discharge, comprising a tube, a middle portion of which is communicated with an intake pipe; discharge coils electrically connected to a matched network and a radio-frequency power supply successively are wound on the tube; one end of the tube is connected to a first cover plate in a sealed manner, and the first cover plate is connected with a positive ion extraction gate via an insulating medium; the positive ion extraction gate is electrically connected to a negative pole of a DC power supply; the other end of the tube is connected to a second cover plate in a sealed manner, the second cover plate is connected to a third cover plate in a sealed manner via a sidewall, and the third cover plate is connected with a negative ion extraction gate via an insulating medium; and the negative ion extraction gate is electrically connected to a positive pole of the DC power supply. In the present invention, the positive ions and the electrons and negative ions can be extracted simultaneously, and the problems of contamination of the ion source by particles sputtered from the backplane and overheating of the backplane are thus solved.

The invention relates to a plasma accelerator that produces and controls a plasma stream exhaust, in particular for space propulsion. The ions are produced inside the discharge chamber by working gas collisional ionization by electrons from a single electron source placed outside, also employed for ion beam neutralization. The ion motion is directed outwards through the exit side by the electric field between a cathode grid and the walls of the plasma chamber. The acceleration voltage imparts energy to the ion flux and an electrically biased control grid modulates the ion outflow from the discharge chamber and the electron inflow from the electron source. This allows electrical control of throttle and/or modulation of thrust delivered along the longitudinal direction of the thruster axis. Several plasma accelerators could be clustered together to provide controlled non-axial thrust using the individual control of throttle.

Method for producing multiply-charged helium nanodroplets and charged dopant clusters and nanoparticles out of the helium nanodroplets, the method comprising: producing neutral helium nanodroplets in a cold head (1) via expansion of a pressurized, pre-cooled, supersonic helium beam of high purity through a nozzle (3) into high vacuum with a base pressure under operation preferably below 20 mPa, ionizing the helium nanodroplets by electron impact (15), wherein the electron impact (15) leads to multiply-charged helium nanodroplets, doping the charged helium nanodroplets with dopant vapor in the pickup cell (19), wherein the doped nanodroplets form cluster ions with the initial charges acting as seeds, wherein the size of the nanoparticles can vary from a few atoms up to 105 atoms by arranging the size of the neutral helium nanodroplets, the charge of the helium nanodroplets and the density of dopant vapor in the pickup cell (19).

The invention relates to a plasma accelerator that produces and controls a plasma stream exhaust, in particular for space propulsion. The ions are produced inside the discharge chamber by working gas collisional ionization by electrons from a single electron source placed outside, also employed for ion beam neutralization. The ion motion is directed outwards through the exit side by the electric field between a cathode grid and the walls of the plasma chamber. The acceleration voltage imparts energy to the ion flux and an electrically biased control grid modulates the ion outflow from the discharge chamber and the electron inflow from the electron source. This allows electrical control of throttle and/or modulation of thrust delivered along the longitudinal direction of the thruster axis. Several plasma accelerators could be clustered together to provide controlled non-axial thrust using the individual control of throttle.

An ion source that is capable of different modes of operation is disclosed. The ion source includes an insertable target holder includes a hollow interior into which the solid dopant material is disposed. The target holder may a porous surface at a first end, through which vapors from the solid dopant material may enter the arc chamber. The porous surface inhibits the passage of liquid or molten dopant material into the arc chamber. The target holder is also constructed such that it may be refilled with dopant material when the dopant material within the hollow interior has been consumed. A solid target is also disposed in the arc chamber. When the insertable target holder is used, multicharged ions are created. When the insertable target holder is retracted, single charged ions are created by only etching the solid dopant-containing compound.

A filament assembly can include: a button having a planar emitter region with one or more apertures extending from an emission surface of the planar emitter region to an internal surface opposite of the emission surface; an inlet electrical lead coupled to the button at a first side; an outlet electrical lead coupled to the button at a second side opposite of the first side; and a low work function object positioned adjacent to the internal surface of the planar emitter region and retained to the button. The planar emitter region can include a plurality of apertures. The low work function object can include a porous ceramic material having the barium, and may have a polished external surface. An electron gun can include the filament assembly. An additive manufacturing system can include the electron gun having the filament assembly.

An ion generator includes an arc chamber which has a plasma generating region therein, a cathode configured to emit a thermoelectron toward the plasma generating region, a repeller which faces the cathode in an axial direction in a state where the plasma generating region is interposed between the cathode and the repeller, and a cage which is disposed to partially surround the plasma generating region at a position between an inner surface of the arc chamber and the plasma generating region.

Example compact ion beam sources are provided that can be used to generate ion beams using chemical species and field emitter elements or field emitter arrays. In some example, the compact ion beam source can be implemented as neutron sources based on ion beam bombardment of neutron-rich targets.