Laser-driven plasmas can accelerate electrons in set-ups far smaller than conventional particle accelerators, but beam divergence is a problem. Here, the authors demonstrate a laser-plasma lens that can focus the beam thanks to field gradients five order of magnitude larger than using traditional optics.
Plasma exists in a mixed form of electrons, positive ions and neutral atoms or molecules and plays an important role in many processes; from astrophysical solar flares to nuclear fusion devices for energy applications. There is a strong research interest both in theory and experiment to understand how the plasma energy is transferred into other forms and how plasma behaves in different environments. Investigating these processes under extreme conditions in a table-top setting has become feasible due to the availability of high-power lasers.
In this collection we highlight a selection of recent experimental and theoretical research papers published on this multidisciplinary topic in Nature Communications. These articles feature research on fundamental plasma processes that are relevant to astrophysical events, energy transfer from laser to the particles during their acceleration, material development for plasma confinement and nuclear reactions in plasma fusion devices. This collection showcases the variety of research that different communities can bring together to better understand the ubiquitous processes in plasma.
Intense laser pulses can induce the propagation of coherent waves through a plasma, which are useful for accelerating electrons. Here, the authors use a genetic algorithm and a deformable mirror to optimize the wavefront and improve electron beam intensity and divergence.
Higher beam quality and stability are desired in laser-plasma accelerators for their applications in compact light sources. Here the authors demonstrate in laser plasma wakefield electron acceleration that the beam loading effect can be employed to improve beam quality by controlling the beam charge.
Extraction of ultra-low emittance bunches is an issue to be addressed for future applications of plasma wakefield accelerators. Here, the authors show that the field structure of the plasma could be suitable for this, by measuring the field's longitudinal variation produced by a relativistic electron bunch.
Single-stage plasma-based correlated energy spread compensation for ultrahigh 6D brightness electron beams
Controlling and improving electron beam parameters are crucial for their application in free electron laser and X-ray sources. Here the authors generate quality electron beams with reduced energy spread from plasma accelerators by using a tailored escort electron bunch with the main accelerating bunch.
Electron–positron pair plasma—a state of matter with a complete symmetry between negatively and positively charged particles—are found in many astrophysical object. Here, the authors use high-power laser to create an ion-free electron–positron plasma in the laboratory.
High power lasers can produce electron-positron pairs at GeV energies, but doing so through laser–laser collisions would require exceedingly high intensities. Here the authors present an all-optical scheme for pair production by irradiating near-critical-density plasmas with two counter-propagating lasers.
Efficient energy transport by laser-driven relativistic electron beams is crucial in many applications including inertial confinement fusion, and particle acceleration. Here the authors demonstrate relativistic electron beam guiding in dense plasma with an externally imposed high magnetic field.
With excellent resolving power and tissue contrast, X-ray phase-contrast imaging holds great promise but the source requirements have limited its use. Here, Wenz et al. show a phase-contrast microtomogram of a biological sample using X-ray radiation driven by a high-power laser.
It is a challenge to scale up laser-ion acceleration to higher ion energies. Here the authors demonstrate a hybrid acceleration scheme based on the relativistic induced transparency mechanism using linearly polarised laser interaction with foil targets and its future implication in using high power lasers.
Towards optical polarization control of laser-driven proton acceleration in foils undergoing relativistic transparency
Intense laser pulse interaction with ultra-thin foils constitutes a promising approach for proton acceleration. Here the authors show that the degree of ellipticity in the laser beam polarization can be used to control the proton beam profile.
Experimental investigations of the response of matter to ionization would require extremely fast ion pump pulses. Here, the authors explore a different approach observing ionisation dynamics in SiO2glass by generating synchronized proton pulses from the interaction of high-power lasers on a solid target.
Neutron beams are useful studying fundamental physics problems, fusion process and material properties. Here the authors use intense laser irradiation of deuterated nanowire array targets to create high energy density plasmas capable of efficient generation of ultrafast neutron pulses.
Table-top laser-plasma ion accelerators have many potential applications, but achieving simultaneous narrow energy spread and high efficiency remains a challenge. Here, the authors produce ion beams with up to 18 MeV per nucleon whilst keeping the energy spread reduced through a self-organized process.
Plasma wakefield accelerators produce gradients that are orders of magnitude larger than in conventional particle accelerator, but beams tend to be disrupted by transverse forces. Here the authors create an extended hollow plasma channel, which accelerates positrons without generating transverse forces.
Recently, there has been significant progress on the application of laser-generated proton beams in material science. Here the authors demonstrate the benefit of employing such beams in stress testing different materials by examining their mechanical, optical, electrical, and morphological properties.
Self-generated surface magnetic fields inhibit laser-driven sheath acceleration of high-energy protons
Laser-generated ion acceleration has received increasing attention due to recent progress in super-intense lasers. Here the authors demonstrate the role of the self-generated magnetic field on the ion acceleration and limitations on the energy scaling with laser intensity.
Electron beam quality in accelerators is crucial for light source application. Here the authors demonstrate beam conditioning of laser plasma electrons thanks to a specific transport line enabling the control of divergence, energy, steering and dispersion and the application to observe undulator radiation.