particle accelerator on a chip ideas

[Jamie M]

Hi,

Based on the recently reported linear particle "accelerator on a chip":

http://news.stanford.edu/news/2013/september/slac-chip-accelerator-092713.html

http://arxiv.org/abs/1308.0464

http://phys.org/news/2013-09-chip.html

http://phys.org/news/2013-10-particles-compact-particle.html

I was thinking about how this could be turned into a circular particle
accelerator instead of a linear accelerator. The linear version seems
to use a glass (or other transparent insulator) with small cogs in it
proportional to the accelerating radiation frequency, so for making a
circular accelerator, it would require this to be a circular gear type
shape, like a change shown in this image from a linear gear to a
circular gear:

http://en.wikipedia.org/wiki/File:Pitches.jpg

For the material used I was thinking a scintillator crystal could be
used that is energized from the center point of the "gear axle" so that
all "teeth" that accelerate the particles will be in phase. There are
other ways to do this, ie with multiple fiber lasers going to gear teeth
sections too.

http://en.wikipedia.org/wiki/Scintillator

Now the electrons will be accelerating, but the problem is they will
want to travel in a straight line, so the gear needs some holding force
to keep them in a circular motion!! At first I was thinking maybe an
adjustable DC bias voltage could be used to hold the particle beam while
it is rotating, but depending on the feedback for the voltage I'm not
sure if this would work?

A simpler new idea I had was to use a different gear tooth design that
automatically will hold the particle beam while it travels around the
circular gear.

This type of herringbone gear design could provide an axial holding
force on the particle beam:

http://en.wikipedia.org/wiki/Herringbone_gear

http://en.wikipedia.org/wiki/File:H...,_Sketches_of_Engine_and_Machine_Details).jpg

This other design of herringbone could provide a radial holding force on
the particle beam:

http://en.wikipedia.org/wiki/File:H..._patent_(Autocar_Handbook,_Ninth_edition).jpg

And for a combined axial+radial holding force on the particle beam, it
is possible to "bend" the already triangular herringbone shape into a
compound triangle shape so that there is radial and axial holding force.

Now when the gear teeth are energized by a laser and the electric field
on them should be able to accelerate the particles and also hold the
particle beam in a focused circular beam at the same time I think!

cheers,
Jamie

 

[Jamie M]

Hi,

Based on the recently reported linear particle "accelerator on a chip":

http://news.stanford.edu/news/2013/september/slac-chip-accelerator-092713.html


http://arxiv.org/abs/1308.0464

http://phys.org/news/2013-09-chip.html

http://phys.org/news/2013-10-particles-compact-particle.html

I was thinking about how this could be turned into a circular particle
accelerator instead of a linear accelerator. The linear version seems
to use a glass (or other transparent insulator) with small cogs in it
proportional to the accelerating radiation frequency, so for making a
circular accelerator, it would require this to be a circular gear type
shape, like a change shown in this image from a linear gear to a
circular gear:

http://en.wikipedia.org/wiki/File:Pitches.jpg

For the material used I was thinking a scintillator crystal could be
used that is energized from the center point of the "gear axle" so that
all "teeth" that accelerate the particles will be in phase. There are
other ways to do this, ie with multiple fiber lasers going to gear teeth
sections too.

http://en.wikipedia.org/wiki/Scintillator

Now the electrons will be accelerating, but the problem is they will
want to travel in a straight line, so the gear needs some holding force
to keep them in a circular motion!! At first I was thinking maybe an
adjustable DC bias voltage could be used to hold the particle beam while
it is rotating, but depending on the feedback for the voltage I'm not
sure if this would work?

A simpler new idea I had was to use a different gear tooth design that
automatically will hold the particle beam while it travels around the
circular gear.

This type of herringbone gear design could provide an axial holding
force on the particle beam:

http://en.wikipedia.org/wiki/Herringbone_gear

http://en.wikipedia.org/wiki/File:H...,_Sketches_of_Engine_and_Machine_Details).jpg


This other design of herringbone could provide a radial holding force on
the particle beam:

http://en.wikipedia.org/wiki/File:H..._patent_(Autocar_Handbook,_Ninth_edition).jpg


And for a combined axial+radial holding force on the particle beam, it
is possible to "bend" the already triangular herringbone shape into a
compound triangle shape so that there is radial and axial holding force.

Now when the gear teeth are energized by a laser and the electric field
on them should be able to accelerate the particles and also hold the
particle beam in a focused circular beam at the same time I think!

cheers,
Jamie

Hi,

Crazy brainstorming mode on:

I think it might also be possible to make one of these ion accelerators
using "virtual teeth" created on a smooth substrate, using surface
plasmonic oscillations that travel and accelerate free ions above the
surface. These traveling wave surface plasmons could be created by
a laser setup, and would provide the moving plasmonic electric field
for the ions to surf. With this type of setup in 2dimensional chip
form, with laser illumination from above, it could be possible to steer
the ions around as well floating a fixed distance above the chip.

An XY grid of plasmonic points that can be energized by the laser could
be used to turn on each grid point "on or off" corresponding to the
plasmonic field at that location, and depending how these are sequenced
would accelerate the ions.

cheers,
Jamie

 

[Jamie M]

The voltage would have to be incredible to keep a high-energy particle traveling
in a circle. A cyclotron or synchrotron uses a magnetic field, which is a little
more manageable. But in order for the mag field strength to be sane, and to
avoid synchrotron radiation losses, you need a big, CERN-sort of radius.

There are tiny accelerators that use electric fields inside crystals... can't
recall what they are called. For neutron sources maybe?

Hi John,

Thanks I forgot about the small diameter issue causing radiation (ie
1meter circumference would give 299MHz synchrotron radiation I guess.

(299,792,458m/s speed of light)

Not sure what the losses would be, I guess they go way up as the
relativistic speed approaches the speed of light though.

So maybe there is no point to making a small circular accelerator!

cheers,
Jamie

 

[Jamie M]

The voltage would have to be incredible to keep a high-energy particle traveling
in a circle. A cyclotron or synchrotron uses a magnetic field, which is a little
more manageable. But in order for the mag field strength to be sane, and to
avoid synchrotron radiation losses, you need a big, CERN-sort of radius.

There are tiny accelerators that use electric fields inside crystals... can't
recall what they are called. For neutron sources maybe?

Hi,

For dealing with the synchrotron radiation losses for a small radius
accelerator, maybe its possible to use some form of regeneration, ie.
capture the emitted radiation and feed it back into the system, still
even if that system was 90% efficient it would be far more losses than
a larger diameter accelerator.

cheers,
Jamie

 

[Jamie M]

Hi,

For dealing with the synchrotron radiation losses for a small radius
accelerator, maybe its possible to use some form of regeneration, ie.
capture the emitted radiation and feed it back into the system, still
even if that system was 90% efficient it would be far more losses than
a larger diameter accelerator.

cheers,
Jamie

Hi,

I just realized if you have two beams of ions traveling in opposite
directions right beside each other that might neutralize the synchrotron
losses, and give a high efficiency regeneration of
the synchrotron losses.

cheers,
Jamie

 

[[email protected]]

Hi,



Based on the recently reported linear particle "accelerator on a chip":



http://news.stanford.edu/news/2013/september/slac-chip-accelerator-092713.html



http://arxiv.org/abs/1308.0464



http://phys.org/news/2013-09-chip.html



http://phys.org/news/2013-10-particles-compact-particle.html



I was thinking about how this could be turned into a circular particle

accelerator instead of a linear accelerator. The linear version seems

to use a glass (or other transparent insulator) with small cogs in it

proportional to the accelerating radiation frequency, so for making a

circular accelerator, it would require this to be a circular gear type

shape, like a change shown in this image from a linear gear to a

circular gear:



http://en.wikipedia.org/wiki/File:Pitches.jpg



For the material used I was thinking a scintillator crystal could be

used that is energized from the center point of the "gear axle" so that

all "teeth" that accelerate the particles will be in phase. There are

other ways to do this, ie with multiple fiber lasers going to gear teeth

sections too.



http://en.wikipedia.org/wiki/Scintillator



Now the electrons will be accelerating, but the problem is they will

want to travel in a straight line, so the gear needs some holding force

to keep them in a circular motion!! At first I was thinking maybe an

adjustable DC bias voltage could be used to hold the particle beam while

it is rotating, but depending on the feedback for the voltage I'm not

sure if this would work?



A simpler new idea I had was to use a different gear tooth design that

automatically will hold the particle beam while it travels around the

circular gear.



This type of herringbone gear design could provide an axial holding

force on the particle beam:



http://en.wikipedia.org/wiki/Herringbone_gear



http://en.wikipedia.org/wiki/File:H...,_Sketches_of_Engine_and_Machine_Details).jpg



This other design of herringbone could provide a radial holding force on

the particle beam:



http://en.wikipedia.org/wiki/File:H..._patent_(Autocar_Handbook,_Ninth_edition).jpg



And for a combined axial+radial holding force on the particle beam, it

is possible to "bend" the already triangular herringbone shape into a

compound triangle shape so that there is radial and axial holding force.



Now when the gear teeth are energized by a laser and the electric field

on them should be able to accelerate the particles and also hold the

particle beam in a focused circular beam at the same time I think!



cheers,

Jamie

Actually, the idea is not new. Decades ago,
a physicist at Univ. oF Texas at Austin, Dr.
Toshiki Tajima, proposed the idea of
acceleration of particles via plasma interaction.
Needless to say, his field of expertise was
plasma physics. Although he has moved to
Japan a few years ago, his work is still
being enhanced by current researcher there
as Dr. Todd Ditmire at the Petawatt Laser
facility at UT.

 

[Jamie M]

Actually, the idea is not new. Decades ago,
a physicist at Univ. oF Texas at Austin, Dr.
Toshiki Tajima, proposed the idea of
acceleration of particles via plasma interaction.
Needless to say, his field of expertise was
plasma physics. Although he has moved to
Japan a few years ago, his work is still
being enhanced by current researcher there
as Dr. Todd Ditmire at the Petawatt Laser
facility at UT.

Hi,

Ya surface plasmons might be a good way to do the acceleration,
if you can get a plasmon wave travelling in a graphene sheet
or tube, that could push along electrons. The surface plasmon
propagation speed is lower than the speed of light, so it would
require some type of sequenced plasmon wave. Like energizing the
graphene in front of the electrons with a laser creating a + charge
area to draw them forward (not sure if that is possible), instead of
relying on the plasmon propagation in the graphene which is too slow.

If you give a carbon nanotube a high electric charge then maybe you can
use it as a particle accelerator tube, so the electron beam inside it
will be repelled by the inner wall of the graphene tube if it has a
high charge, which might allow for bending paths. An electromagnetic
field could be used to vary the charge on the tube for accelerating the
electrons, but it would have an overall negative bias too.

Just more crazy ideas!

cheers,
Jamie

 

[Jamie M]

Hi,

Ya surface plasmons might be a good way to do the acceleration,
if you can get a plasmon wave travelling in a graphene sheet
or tube, that could push along electrons. The surface plasmon
propagation speed is lower than the speed of light, so it would
require some type of sequenced plasmon wave. Like energizing the
graphene in front of the electrons with a laser creating a + charge
area to draw them forward (not sure if that is possible), instead of
relying on the plasmon propagation in the graphene which is too slow.

If you give a carbon nanotube a high electric charge then maybe you can
use it as a particle accelerator tube, so the electron beam inside it
will be repelled by the inner wall of the graphene tube if it has a
high charge, which might allow for bending paths. An electromagnetic
field could be used to vary the charge on the tube for accelerating the
electrons, but it would have an overall negative bias too.

Just more crazy ideas!

cheers,
Jamie

This page shows a new way to make holograms from an array of nano
antennas energized by a laser:

http://phys.org/news/2013-11-hologram-technology-tiny-nanoantennas.html

This could also be used potentially as an ion accelerator, but the
electric field of the light would be a lot less than the field in the
toothed design, similar to an ironless stator vs an iron backed stator
in an electric motor.

cheers,
Jamie