Laser Wakefield plasma acceleration of electrons to energies above 10 GeV, may be possible in the new high power Laser beam facilities. The design of an Electron Spectrometer with an electro-magnet with adjustable mag...Laser Wakefield plasma acceleration of electrons to energies above 10 GeV, may be possible in the new high power Laser beam facilities. The design of an Electron Spectrometer with an electro-magnet with adjustable magnetic field is proposed for the characterization of electron energy spectrum with a precision better than 10% for the entire energy range from 0.5 GeV to 38 GeV. The expected precision in the measurement of the electron energy is calculated as a function of the magnetic field, of the electron energy and of the magnet length. To outline the advantages offered by a pulsed electromagnet with high magnetic fields, the mass and the electric power lost in the coils of a 4 m long electromagnet with continuous current and Iron yoke are calculated.展开更多
Based on the inverse Faraday effect, a super-long longitudinal magnetization needle can be induced by a trans- versely polarized needle-shaped electric field. This needle-shaped electric field can be obtained in the f...Based on the inverse Faraday effect, a super-long longitudinal magnetization needle can be induced by a trans- versely polarized needle-shaped electric field. This needle-shaped electric field can be obtained in the focal vol- ume of the objective by focusing an azimuthally polarized vortex beam that is modulated both radially and azimuthally by a specifically designed annular phase filter. The numerical calculation shows that the full widths at half-maximums in longitudinal direction and in transverse direction of the magnetization needle are 282 and 0.27λ. The corresponding needle aspect ratio of 103 is more than ten times larger than that of the magnetization needle fabricated by electron beam lithography.展开更多
文摘Laser Wakefield plasma acceleration of electrons to energies above 10 GeV, may be possible in the new high power Laser beam facilities. The design of an Electron Spectrometer with an electro-magnet with adjustable magnetic field is proposed for the characterization of electron energy spectrum with a precision better than 10% for the entire energy range from 0.5 GeV to 38 GeV. The expected precision in the measurement of the electron energy is calculated as a function of the magnetic field, of the electron energy and of the magnet length. To outline the advantages offered by a pulsed electromagnet with high magnetic fields, the mass and the electric power lost in the coils of a 4 m long electromagnet with continuous current and Iron yoke are calculated.
文摘Based on the inverse Faraday effect, a super-long longitudinal magnetization needle can be induced by a trans- versely polarized needle-shaped electric field. This needle-shaped electric field can be obtained in the focal vol- ume of the objective by focusing an azimuthally polarized vortex beam that is modulated both radially and azimuthally by a specifically designed annular phase filter. The numerical calculation shows that the full widths at half-maximums in longitudinal direction and in transverse direction of the magnetization needle are 282 and 0.27λ. The corresponding needle aspect ratio of 103 is more than ten times larger than that of the magnetization needle fabricated by electron beam lithography.
