Computer implemented design of device for electro-optical modulation of light incident upon device

An apparatus comprising a computer program product, said computer program product comprising a computer readable memory device having a computer readable program code embodied therein, said computer readable program code containing instructions configured to be executed by a processor of a computer system to implement a method for designing an electro-optical modulator device to operate in a coupling mode or a detection mode in which light having a wavelength λ is incident upon a semiconductor structure comprised by the electro-optical modulator device at an incident angle (θi) with respect to a direction opposite to a Z direction, said method comprising

• said processor receiving input for designing the electro-optical modulator device to operate in the coupling mode or the detection mode, wherein the semiconductor structure comprises a semiconductor layer having a thickness (r) in the Z direction and a plurality of grating structures on a top surface of the semiconductor layer, wherein the Z direction is perpendicular to the top surface of the semiconductor layer, wherein the semiconductor layer comprises a plurality of semiconductor channel regions, wherein the grating structures are distributed in a periodic pattern having a pitch (p1) in an X direction that is orthogonal to the Z direction, wherein each grating structure comprises a notch and is above a corresponding channel region of the plurality of semiconductor channel regions and has a height (hg) in the Z direction above the top surface of the semiconductor layer, wherein each notch comprises a width (w1) in the X direction, wherein a voltage V applied between each notch and a corresponding doped semiconductor region in the semiconductor layer induces a change Δa of an absorption coefficient (a) and a change Δn of an index of refraction of a semiconductor domain comprising each notch and its corresponding channel region to generate a changed absorption coefficient and a changed index of refraction of the semiconductor domain, and wherein said receiving input comprises receiving a value of λ, r, hg, an absorption coefficient threshold (Ath1), an index of refraction threshold (nth1), and acceptance criteria;
• said processor ascertaining P solution sets at which the electro-optical modulator device operates in an ON state in which V=V1 for causing the changed absorption coefficient to exceed Ath1 and causing the changed index of refraction to exceed nth1 and at which the acceptance criteria are satisfied, wherein said ascertaining comprises calculating Δa according to Δa(V) and calculating Δn according to Δn(V), wherein Δa(V) is a specified function of V and Δn(V) is a specified function of V, wherein each solution set of the P solution sets comprises p1, w1, θi, and V1, and wherein P≧1;
• determining a design set for the ON state;
• said processor transmitting the design set for the ON state to an output device.

A method for designing an electro-optical modulator device to operate in a reflection mode in which light having a wavelength λ is incident upon a semiconductor structure comprised by the electro-optical modulator device at an incident angle (θi) with respect to a direction opposite to a Z direction, said method comprising:

• receiving input, by a processor of a computer system, for designing the electro-optical modulator device to operate in the reflection mode, wherein the semiconductor structure comprises a semiconductor layer having a thickness (r) in the Z direction and a plurality of grating structures on a top surface of the semiconductor layer, wherein the Z direction is perpendicular to the top surface of the semiconductor layer, wherein the semiconductor layer comprises a plurality of semiconductor channel regions, wherein the grating structures are distributed in a periodic pattern having a pitch (p1) in an X direction that is orthogonal to the Z direction, wherein each grating structure comprises a notch and is above a corresponding channel region of the plurality of semiconductor channel regions and has a height (hg) in the Z direction above the top surface of the semiconductor layer, wherein each notch comprises a width (w1) in the X direction, wherein a voltage V applied between each notch and a corresponding doped semiconductor region in the semiconductor layer induces a change Δa of an absorption coefficient and a change Δn of an index of refraction of a semiconductor domain comprising each notch and its corresponding channel region to generate a changed absorption coefficient (a), a changed index of refraction (n), and a change in an optical path length (ΔOPL) of the semiconductor domain, wherein ΔOPL=(2π/λ)*Δn*δr, wherein δr is a total physical path length of the semiconductor domain traversed by the light incident upon the semiconductor structure at the angle θi, and wherein said receiving input comprises receiving a value of λ, r, hg, an absorption coefficient threshold (Ath0), index of refraction thresholds (n0min and n0max) such that n0min<n0max, and acceptance criteria;
• said processor ascertaining P solution sets at which the electro-optical modulator device operates in an OFF state in which V=V0 for causing ΔOPL=λ/2 to be satisfied and causing the absorption coefficient of the semiconductor domain to be less than Ath0 and causing the index of refraction of the semiconductor domain to be in a range of n0min to n0max and at which the acceptance criteria are satisfied, wherein said ascertaining comprises calculating Δn according to Δn(V) and calculating δr via geometric ray tracing of the light through the semiconductor domain for the incident angle θi, wherein Δn(V) is a specified function of V, wherein each solution set of the P solution sets comprises p1, w1, θi, and V0, and wherein P≧1;
• said processor determining a design set for the OFF state,
• said processor transmitting the design set for the OFF state to an output device.

An apparatus comprising a computer program product, said computer program product comprising a computer readable memory device having a computer readable program code embodied therein, said computer readable program code containing instructions configured to be executed by a processor of a computer system to implement a method for designing an electro-optical modulator device to operate in a reflection mode in which light having a wavelength λ is incident upon a semiconductor structure comprised by the electro-optical modulator device at an incident angle (θi) with respect to a direction opposite to a Z direction, said method comprising:

• said processor receiving input for designing the electro-optical modulator device to operate in the reflection mode, wherein the semiconductor structure comprises a semiconductor layer having a thickness (r) in the Z direction and a plurality of grating structures on a top surface of the semiconductor layer, wherein the Z direction is perpendicular to the top surface of the semiconductor layer, wherein the semiconductor layer comprises a plurality of semiconductor channel regions, wherein the grating structures are distributed in a periodic pattern having a pitch (p1) in an X direction that is orthogonal to the Z direction, wherein each grating structure comprises a notch and is above a corresponding channel region of the plurality of semiconductor channel regions and has a height (hg) in the Z direction above the top surface of the semiconductor layer, wherein each notch comprises a width (w1) in the X direction, wherein a voltage V applied between each notch and a corresponding doped semiconductor region in the semiconductor layer induces a change Δa of an absorption coefficient and a change Δn of an index of refraction of a semiconductor domain comprising each notch and its corresponding channel region to generate a changed absorption coefficient (a), a changed index of refraction (n), and a change in an optical path length (ΔOPL) of the semiconductor domain, wherein ΔOPL=(2π/λ)*Δn*δr, wherein δr is a total physical path length of the semiconductor domain traversed by the light incident upon the semiconductor structure at the angle θi, and wherein said receiving input comprises receiving a value of λ, r, hg, an absorption coefficient threshold (Ath0), index of refraction thresholds (n0min and n0max) such that n0min<n0max, and acceptance criteria;
• said processor ascertaining P solution sets at which the electro-optical modulator device operates in an OFF state in which V=V0 for causing ΔOPL=λ/2 to be satisfied and causing the absorption coefficient of the semiconductor domain to be less than Ath0 and causing the index of refraction of the semiconductor domain to be in a range of n0min to n0max and at which the acceptance criteria are satisfied, wherein said ascertaining comprises calculating Δn according to Δn(V) and calculating δr via geometric ray tracing of the light through the semiconductor domain for the incident angle θi, wherein Δn(V) is a specified function of V, wherein each solution set of the P solution sets comprises p1, w1, θi, and V0, and wherein P≧1;
• said processor determining a design set for the OFF state;
• said processor transmitting the design set for the OFF state to an output device.