Plasma mass separator using ponderomotive forces
AssigneeArchimedes Technology Group, Inc.
InventorTihiro Ohkawa
Life of this patent
Estimating the term…
Abstract
A device for separating high-mass ions (having cyclotron frequency Ωh) from low-mass ions (having cyclotron frequency Ωl) in a plasma includes a chamber. Coils are provided to generate a substantially uniform magnetic field in the chamber. An antenna is provided to launch a left-hand elliptically polarized electromagnetic wave into the chamber along the stationary magnetic field that is evanescent in the multi-species plasma. Importantly, the E vector of the elliptically polarized electromagnetic wave rotates at a frequency, ω, where Ωh<ω<Ωl. Ponderomotive forces are generated by the electromagnetic wave that cause the low-mass ions to move toward the antenna while causing the high-mass ions to move away from the antenna.
Claims13
A device for separating ions of a multi-species plasma in a plasma chamber using ponderomotive forces which comprises:
- means for generating a substantially uniform magnetic field in the plasma chamber, said magnetic field having a magnitude B and a direction;
- means for introducing said multi-species plasma into said plasma chamber, said multi-species plasma including ions of a relatively high-mass charge ratio (Mh) having a cyclotron frequency (Ωh) and ions of a relatively low-mass charge ratio (MI) having a cyclotron frequency (ΩI);
- an antenna for propagating an electromagnetic wave into the plasma chamber substantially in the direction of said magnetic field;
- means for rotating the electromagnetic wave at a frequency ω with a left-hand polarized mode relative to the electron gyration;
- and
- means for tuning said frequency ω of the electromagnetic wave, with Ωh<ω<ΩI, to establish an evanescence of the electromagnetic wave in the multi-species plasma and generate respective oppositely directed ponderomotive forces on said ions Mh and Ml for separating said ions from each other.
A device for separating ions of a multi-species plasma in a plasma chamber using ponderomotive forces, said device comprising:
- means for generating a magnetic field in said plasma chamber;
- means for introducing said multi-species plasma into said plasma chamber, said multi-species plasma including ions of relatively high-mass to charge ratio having a cyclotron frequency (Ωh) and ions of relatively low-mass to charge ratio having a cyclotron frequency (ΩI);
- and
- means for launching an electromagnetic wave that is evanescent in the multi-species plasma into the plasma chamber, said electromagnetic wave being left-hand elliptically polarized and having a frequency, ω, with Ωh<ω<ΩI, to generate respective oppositely directed ponderomotive forces on said ions of relatively high-mass to charge ratio and said ions of relatively low-mass to charge ratio for separating said ions of relatively low-mass to charge ratio from said ions of relatively high-mass to charge ratio.
Dependencies are inferred from the claim text.