Single‐Lens Counter‐Focused Ultrashort Laser Pulses for Enhanced Microplasma Formation Inside Silicon
The polarization‐dependent diffraction efficiency inherent to liquid‐crystal spatial light modulators (SLM) is exploited to create coaxial double‐focus laser beams. The axial separation and peak‐intensity balance between the beam foci are independently controlled by actively tuning the encoded quadratic phase hologra...