The present disclosure is directed to laser apparatuses for generating coherent
electromagnetic laser radiation having an electron beam generator, a diffraction
grating element oriented such that a beam of electrons from the electron beam generator
is directed over the diffraction grating element, and at least one wing element
coupled to the diffraction grating element. In some embodiments, the wing element(s)
can be coupled to a top portion of the diffraction grating element. While in others,
the wing element(s) can be coupled to a side portion of the diffraction grating
element. The present disclosure is also directed to methods of manufacturing diffraction
grating elements involving placing at least one secondary conducting sheet having
a first height on at least one primary conductive sheet having a different second
height, and securing the primary and secondary conductive sheets together. The
primary and secondary conductive sheets can be alternating and their thicknesses
may also be different. Additionally, the primary and secondary conductive sheets
may be secured via a clamping device.