A silicon-based optical modulating device comprising: a silicon body layer doped to exhibit a first conductivity type; a silicon gate layer doped to exhibit a second conductivity type, the silicon gate layer having an overlapping portion (2-A) disposed at least in part to overlap an overlapping portion (3-A) of the silicon body layer to define a contiguous area between said silicon body and gate layers (3, 2); a thin dielectric layer disposed in the contiguous area between said overlapping portions (3-A, 2-A) of the silicon body and gate layers (3, 2), the combination of said overlapping portions (3-A, 2-A) of the silicon body and gate layers (3, 2) with the interposed relatively thin dielectric layer defining an active region of the optical modulating device where carrier modulation occurs; a first electrical contact coupled to an outer, contact portion (2-C) of the silicon gate layer; and a second electrical contact coupled to an outer, contact portion (3-A) of the silicon body layer, wherein upon application of an electrical signal to the first and second electrical contacts, free carriers accumulate, deplete or invert within the contiguous areas of the overlapping portions (3-A, 2-A) of the silicon body and gate layers (3, 2) on both sides of the thin dielectric layer, such that an optical intensity of an optical signal propagating along a waveguide defined by the active region overlaps with the free carrier concentration modulation area in the active region of said optical modulating device, where the overlapping portions (2-A, 3-A) of the silicon body and gate layers (3, 2) are doped to exhibit a lowest dopant concentration in the active region and the outer, contact portions (3-C, 2-C) of the silicon body and gate layers (3, 2) are doped to exhibit a highest dopant concentration, with at least one of the silicon body and gate layers (3, 2), characterized by further exhibiting an intermediate dopant concentration in an intermediate region (3-1, 2-1) between the respective overlapping region (3-A, 2-A) and the respective outer, contact portion (3-C, 2-C), wherein the intermediate region (3-1, 2-1) comprises a dopant concentration that decreases in value from the respective contact region (3-C, 2-C) to the respective overlapping portion (3-A, 2-A), wherein the dopant concentration is inversely related to the optical intensity in the intermediate region (3-1, 2-1). a silicon body layer doped to exhibit a first conductivity type; a silicon gate layer doped to exhibit a second conductivity type, the silicon gate layer having an overlapping portion (2-A) disposed at least in part to overlap an overlapping portion (3-A) of the silicon body layer to define a contiguous area between said silicon body and gate layers (3, 2); a thin dielectric layer disposed in the contiguous area between said overlapping portions (3-A, 2-A) of the silicon body and gate layers (3, 2), the combination of said overlapping portions (3-A, 2-A) of the silicon body and gate layers (3, 2) with the interposed relatively thin dielectric layer defining an active region of the optical modulating device where carrier modulation occurs; a first electrical contact coupled to an outer, contact portion (2-C) of the silicon gate layer; and