The availability of ever stronger,laser-generated electromagnetic fields underpins continuing progress in the study and application of nonlinear phenomena in basic physical systems,ranging from molecules and atoms to ...The availability of ever stronger,laser-generated electromagnetic fields underpins continuing progress in the study and application of nonlinear phenomena in basic physical systems,ranging from molecules and atoms to relativistic plasmas and quantum electrodynamics.This raises the question:how far will we be able to go with future lasers?One exciting prospect is the attainment of field strengths approaching the Schwinger critical field Ecr in the laboratory frame,such that the field invariant E^(2)−c^(2)B^(2)>E_(cr)^(2) is reached.The feasibility of doing so has been questioned,on the basis that cascade generation of dense electron–positron plasma would inevitably lead to absorption or screening of the incident light.Here we discuss the potential for future lasers to overcome such obstacles,by combining the concept of multiple colliding laser pulses with that of frequency upshifting via a tailored laser–plasma interaction.This compresses the electromagnetic field energy into a region of nanometre size and attosecond duration,which increases the field magnitude at fixed power but also suppresses pair cascades.Our results indicate that laser facilities with peak power of tens of PW could be capable of reaching Ecr.Such a scenario opens up prospects for the experimental investigation of phenomena previously considered to occur only in the most extreme environments in the universe.展开更多
基金This research was supported by the Swedish Research Council Grants Nos.2016-03329 and 2020-06768(T.G.B.and M.M.)2017-05148(A.G.),as well as the U.S.Department of Energy Office of Science Offices of High Energy Physics and Fusion Energy Sciences(through LaserNetUS)+1 种基金under Contract No.DE-AC02-05CH11231(S.S.B.)Simulations were performed on resources provided by the Swedish National Infrastructure for Computing(SNIC).
文摘The availability of ever stronger,laser-generated electromagnetic fields underpins continuing progress in the study and application of nonlinear phenomena in basic physical systems,ranging from molecules and atoms to relativistic plasmas and quantum electrodynamics.This raises the question:how far will we be able to go with future lasers?One exciting prospect is the attainment of field strengths approaching the Schwinger critical field Ecr in the laboratory frame,such that the field invariant E^(2)−c^(2)B^(2)>E_(cr)^(2) is reached.The feasibility of doing so has been questioned,on the basis that cascade generation of dense electron–positron plasma would inevitably lead to absorption or screening of the incident light.Here we discuss the potential for future lasers to overcome such obstacles,by combining the concept of multiple colliding laser pulses with that of frequency upshifting via a tailored laser–plasma interaction.This compresses the electromagnetic field energy into a region of nanometre size and attosecond duration,which increases the field magnitude at fixed power but also suppresses pair cascades.Our results indicate that laser facilities with peak power of tens of PW could be capable of reaching Ecr.Such a scenario opens up prospects for the experimental investigation of phenomena previously considered to occur only in the most extreme environments in the universe.
