Method and device for spatial charged particle bunching

A charged particle buncher comprising:

• a series of spaced apart electrodes arranged to generate a time varying longitudinal electric field profile changing on a timescale equivalent to the mean transit time of a beam of charged particles traversing the gaps between adjacent electrodes, the series comprising a first electrode, a last electrode and one or more intermediate electrodes;
• and
• a voltage source attached to each electrode independently configured to generate a voltage gradient that emulates a travelling electric field signal within the gaps between adjacent electrodes in such a manner to form a first polarity of the electric field between adjacent electrodes within one or more groupings of electrodes, the first polarity configured to bunch charged particles passing through the first polarity by accelerating a first portion of the charged particles and/or by decelerating a second portion of charged particles, and a second polarity of the electric field between adjacent electrodes within one or more remaining groupings of electrodes, the second polarity configured to adjust the acceleration rate of the first portion and second portion of charged particles so that substantially all the particles within the bunch have a net zero acceleration with respect to the bunch;
• wherein the potential gradient amplitude within each gap changes on a timescale equal to the mean transit time of a beam of charged particles traversing the gaps between adjacent electrodes and wherein the resultant time varying overall electric field waveform applies an axial force distribution to the charged particles as they traverse all the groups of electrodes with the different polarities to produce a near net zero acceleration of the bunched charged particles and a spatial and temporal redistribution of the charged particles in the beam at the exit plane of the device to form a fixed pattern of a plurality of bunched travelling particle beam segments and nonbunched traveling particle beam segments, wherein the bunched particles have a spatially uniform charged particle density and the nonbunched particle beam segments have substantially no charged particle density;
• and at least one ion source preceding the series of electrodes and followed by a biological material.