ELFT HÍRADÓ

[Szeminárium koordinátor <szfi-seminar AT wigner.mta.hu>]

WIGNER SZFI Seminar

Klein-Gordon radio and attosecond light pulses

Varró Sándor
MTA Wigner FK SZFI, Budapest and ELI-ALPS, Szeged

Tuesday, 7 May 2019 10:00, KFKI Campus, Bldg. 1, 2nd floor, Conference Room

We will show that the four potential of electromagnetic fields in a plasma medium can be considered as a massive vector boson field, where the mass is proportional to the plasma frequency. Similar vector fields have long been known in quantum electrodynamics from the works of Lánczos and Proca, but these do not rely on plasma considerations. The mass-generation mechanism has been described by Anderson in solid state physics, and the research in particle physics on this subject has recently culminated in the detection of the Higgs particle.

The plane waves of the Lánczos-Proca fields have three orthogonal polarizatons, whose amplitudes satisfy the Klein-Gordon equation. The _expression_ "Klein-Gordon radio” in our title has been borrowed from the paper by Crandall and Wheeler [1], on a dynamical bound on photon mass. These authors presented the peculiarities of wave propagation in free space, such as the appearance of wake-fields and the special Doppler effect of radio signals from a rapidly receding massy-photon transmitter. We show that similar phenomena are also relevant in laser wake-field accelerators and in the generation of high harmonics (and attosecond pulses) by relativistic electrons, interacting with extremely high intensity laser fields in a plasma environment. On the basis of recently found exact solutions of the relativistic wave equations of charged particles [2], we also show that very high contrast density modulations are generated, serving as "quantum bubbles" to accelerate electrons [3]. In the last part of the talk we consider exact analytic solutions of the relativistic equation of motion of a point electron interacting with a high-intensity laser field in vacuum [4] and in a plasma medium, and compare the particle dynamics (laser acceleration) and the radiation properties (attosecond light pulse generation) in these two cases. 

[1] Crandall R E, Wheeler N A, Nuovo Cim. 80B, 231-242 (1984).
[2] Varró S,  Nucl. Instr. and Methods in Phys. Research A  740, 280-283 (2014).
[3] Varró S,  EUCALL Joint Foresight Topical Workshop [ELI-ALPS, 1-6 July 2018, Szeged, Hungary].
[4] Hack Sz, Varró S and Czirják A,  New J. Phys. 20, 073043 (2018).

 

Everyone is welcome to attend.

János Asbóth
szfi-seminar AT wigner.mta.hu