Electron beam modulation device and electron beam modulation method
An electron beam modulation device according to the present disclosure includes a light source configured to emit laser light, a polarization conversion part including a modulation plane configured to modulate a direction of polarization and an intensity of the laser light emitted from the light source, and a condensing element configured to condense the laser light passing through the modulation plane. In a focal plane of the condensing element, a round light is generated that includes a trapping potential region in which electrons included in an electron beam incident on the focal plane are attracted and a repulsive potential region in which the electrons are repelled. The round light has rotational symmetry about an optical axis of the laser light when viewed along the optical axis.
1 . An electron beam modulation method comprising:
modulating a direction of polarization and an intensity of laser light emitted from a light source to a predetermined directional distribution and a predetermined intensity distribution, respectively;
condensing, by a condensing element, the laser light modulated to generate round light including a trapping potential region in which electrons are attracted and a repulsive potential region in which the electrons are repelled, the round light having rotational symmetry about an optical axis of the laser light when viewed along the optical axis; and
modulating an electron beam incident on the round light in accordance with a distribution of the trapping potential region and the repulsive potential region.