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In this excellent answer by Emilio Pisanty, he states that:

Of course, all the cool laser-driven QED stuff at the top of that second diagram: if your laser is strong enough that, if you release an electron into the focus, the kinetic energy of its oscillations will exceed $m_ec^2$ , then you can start to have things like laser-driven pair creation, and all sorts of fun stuff. Some of it is already on the table, some of it is in achievable plans for the future, and all of it is made possible by CPA.

Here does the mention of laser-driven pair creation mean that Chirped Pulse Amplification can be used for producing electron-antielectron pairs?

A few weeks ago, I asked in the chat room whether it is possible to produce electron-positron pairs from light. @John Rennie replied, that you can, but the probability is extremely low. So, I had a doubt whether CPA can be used to raise those odds; of course, I may be seriously wrong and could have misunderstood the above statement, but is this possible.

If this is, then maybe we can use electromagnetic fields to separate the two particles and obtain antimatter.

So, boiling down:

The actual Questions:

  1. Can CPA be used to produce electron-positron pairs, with an acceptable probability of pair production happening?
  2. Would those particles be actual particles or virtual particles?
  3. Can we use it to create antimatter?
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  • $\begingroup$ I would just like to add that CPA, although was what enabled a lot of progress in ultrafast optics, is not necessarily the only way to achieve high peak powers. In other words, this question should not ask "if CPA can", it should be more "what is expected from current state-of-the-art light sources, or next generation", or simply, "can light etc." $\endgroup$ – José Andrade Jun 28 '20 at 17:50
  • $\begingroup$ Yeah that is what I meant. It's not just about current technological level, but CPA in general. Whether, at any point we would be able to achieve pair production. $\endgroup$ – PNS Jun 29 '20 at 2:42
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Can CPA be used to produce electron-positron pairs, with an acceptable probability of pair production happening?

Yes, it can $-$ at least in principle. Electrons accelerated by a strong-enough light field acquire sufficient kinetic energy to power pair creation, and if the energy is available then it will indeed happen (though you might need this electron to collide with something else to avoid certain selection rules that might suppress the process).

This would indeed produce real (i.e. not virtual) electron-positron pairs, and as such it would whisk antimatter into being. However, there are currently no prospects in which this antimatter could be captured or used downstream.

It's important to note that thus far this is still only something that is possible in principle, and this capability is still under development. From what I understand, there are beamlines looking to achieve these intensities in both ELI Beamlines and ELI-NP -- keep an eye out on them if you want to see how things develop.

Relevant reference: Optics in the relativistic regime, G. Mourou et al., Rev. Mod. Phys. 78, 309 (2006).

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  • $\begingroup$ Thanks for the answer! $\endgroup$ – PNS Jul 21 '20 at 2:48

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