A p-type MOSFET of a CMOS structure has a silicon-germanium alloy channel to which a longitudinal compressive stress is applied by embedded epitaxial silicon-germanium alloy source and drain regions comprising a silicon-germanium alloy having a higher concentration of germanium than the channel of the p-type MOSFET. The firearm mount is shaped to receive and lockably secure a firearm. Adding this fourth element makes it possible to adjust the width of the forbidden band, the conduction band discontinuity Ec, and the valance band discontinuity Ev of the heterojunction. The at least one passive optical component comprises a transparent element having two opposing approximately flat surfaces substantially perpendicular to a vertical direction in a distance approximately equal to a thickness of the at least one blocking portion measured along the vertical direction, and, attached to the transparent element, at least one optical structure.