Generation and acceleration of charged particles using compact devices and systems

Patent metadata

Field	Value
Publication number	US-9867272-B2
Application number	US-201314436859-A
Country	US
Kind code	B2
Filing date	Oct 17, 2013
Priority date	Oct 17, 2012
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

A system that generates short charged particle packets or pulses (e.g., electron packets) without requiring a fast-switching-laser source is described. This system may include a charged particle source that produces a stream of continuous charged particles to propagate along a charged particle path. The system also includes a charged particle deflector positioned in the charged particle path to deflect the stream of continuous charged particles to a set of directions different from the charged particle path. The system additionally includes a series of beam blockers located downstream from the charged particle deflector and spaced from one another in a linear configuration as a beam-blocker grating. This beam-blocker grating can interact with the deflected stream of charged particles and divide the stream of the charged particles into a set of short particle packets. In one embodiment, the charged particles are electrons. The beam blockers can be conductors.

First claim

What is claimed is:

1. A device for accelerating charged particles, comprising:
a radio frequency (RF) signal generator for generating an RF signal;
an RF resonator coupled to the RF signal generator and operable to generate a high-voltage RF drive signal based on the received RF signal; and
a linear series of electrode segments arranged to form a path for receiving and accelerating charged particles and coupled to the RF resonator to receive the high-voltage RF drive signal to accelerate received charged particles successively through the linear series of electrode segments, wherein each electrode segment of the linear series of electrode segments is driven by the high-voltage RF drive signal, and wherein the path formed by the linear series of electrode segments has a different, non-parallel direction from that of the received charged particles.

2. The device of claim 1 , wherein the RF resonator is implemented as a coplanar waveguide.

3. The device of claim 2 , wherein the coplanar waveguide is configured in a meander structure to match the wavelength of the RF resonator.

4. The device of claim 2 , wherein the coplanar waveguide is formed on one of:
a printed circuit board (PCB);
Rogers material;
Alumina;
Sapphire; or
a ceramic substrate.

5. The device of claim 2 , wherein the coplanar waveguide and the linear series of electrode segments are formed on a common planar platform.

6. The device of claim 2 , wherein the coplanar waveguide is substantially parallel to the linear series of electrode segments.

7. The device of claim 2 , wherein the linear series of electrode segments are raised above the coplanar waveguide to minimize the electric field between the ground of the coplanar waveguide and the electric potential of the linear series of electrode segments.

8. The device of claim 1 , wherein the linear series of electrode segments are coupled to the RF resonator through a set of wire bonds.

9. The device of claim 1 , wherein the linear series of electrode segments are coupled to the RF resonator through printed conductor wires or planar waveguides.

10. The device of claim 1 , wherein the linear series of electrode segments are spaced by a set of gaps of a constant size.

11. The device of claim 1 , wherein the linear series of electrode segments serves the function of traditional drift tubes in a linear particle accelerator (LINAC).

12. The device of claim 1 , wherein each electrode segment in the linear series of electrode segments comprises a pair of parallel electrode blocks, and wherein the space between the pair of parallel electrode blocks is part of the path for receiving and accelerating the charged particles.

13. The device of claim 12 , wherein each of the pair of parallel electrode blocks is a multi-layer stack comprising multiple silicon/metal-multilayer structures.

14. The device of claim 1 , wherein the RF resonator generates the high-voltage RF drive signal by multiplying the amplitude of the received RF signal by a factor less than or equal to the quality (Q) factor of the RF resonator.

15. The device of claim 1 , wherein the frequency of the RF signal is selected to match the transit time of the charged particles through a single electrode segment stage within the linear series of electrode segments.

16. The device of claim 1 , wherein the path of the linear series of electrode segments is fabricated by a laser-micromachining process or a Deep Reactive Ion Etching (DRIE) process.

17. The device of claim 1 , further comprising an RF amplifier coupled between the RF signal generator and the RF resonator for amplifying the RF signal.

18. The device of claim 1 , wherein the linear series of electrode segments is further subjected to a DC bias voltage.

19. A LINAC for accelerating charged particles, comprising:
a radio frequency (RF) signal generator for generating an RF signal;
an RF resonator coupled to the RF signal generator and operable to generate a high-voltage RF drive signal based on the received RF signal; and
a linear series of drift tubes for receiving and accelerating charged particles and coupled to the RF resonator to receive the high-voltage RF drive signal to accelerate received charged particles successively through the linear series of drift tubes, wherein each drift tube of the linear series of conventional drift tubes is driven by the high-voltage RF drive signal, and wherein the linear series of drift tubes are arranged to form a path to receive the charged particles in a direction different and non-parallel from that of the accelerated charged particles accelerated by drift tubes.

20. The LINAC of claim 19 , wherein the RF resonator is implemented as a coplanar waveguide on a PCB.

21. The LINAC of claim 19 , wherein the RF resonator generates the high-voltage RF drive signal by multiplying the amplitude of the received RF signal by a factor less than or equal to the quality (Q) factor of the RF resonator.

22. A device for accelerating charged particles, comprising:
a radio frequency (RF) signal generator for generating an RF drive signal; and
a linear series of electrode segments to form a path for receiving and accelerating charged particles and coupled to the RF resonator to receive the RF drive signal to accelerate received charged particles successively through the linear series of electrode segments, wherein each electrode segment of the linear series of electrode segments is driven by the RF drive signal, and wherein the linear series of electrode segments are micro-fabricated using a wafer technology, and wherein the path formed by the linear series of electrode segments has a different, non-parallel direction from that of the received charged particles.

Assignees

• Univ Cornell

Inventors

• Lal Amit
• Shi Yue
• Ardanuc Serhan
• Hwang June-Ho
• Rana Farhan

Classifications

• H05H9/042

  Drift tube LINACS · CPC title

• H05H9/045 Primary

  Radio frequency quadrupoles · CPC title

• H01J2237/063

  Electron sources · CPC title

• H01J37/06

  Electron sources; Electron guns · CPC title

• H01J37/1472

  Deflecting along given lines · CPC title