Waveguides and devices incorporating optically functional cladding regions

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction alone an x axis perpendicular to said z axis, and a second cladding region offset from said z axis in a second direction along said x axis, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second cladding regions are poled in opposite directions;
• and
• said waveguide core defines a cross-sectional x axis width that decreases from a region outside of said first and second cladding regions to a region bounded by said first and second cladding regions.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, and a second cladding region offset from said z axis in a second direction alone said x axis, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electronic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second cladding regions are poled in opposite directions;
• and
• said optical waveguide core comprises a doped silica waveguide and said refractive index n1is about 1.45 at 1550 nm.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, and a second cladding region offset from said z axis in a second direction along said x axis, wherein:

• said optical waveguide core comprises a substantially now-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second cladding regions are poled in opposite directions;
• and
• said first and second cladding regions comprise a common electrooptic polymer.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction alone an x axis perpendicular to said z axis, and a second cladding region offset from said z axis in a second direction along said x axis, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second cladding regions are poled in Opposite directions;
• and
• the refractive index of the first cladding region is equal to the refractive index of the second cladding region.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, and a second cladding region offset from said z axis in a second direction along said x axis, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• and
• said first arid second cladding regions are poled in perpendicular directions.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, a second cladding region offset from said z axis in a second direction along said x axis, and first and second control electrodes, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second control electrodes are arranged to enable electrooptic modification of said refractive indices of said first and second cladding regions by creating a contoured electric field in said first and second cladding regions;
• said contoured electric field and said respective directions of polarization in said first and second cladding regions define a polarization-independent waveguide structure along said primary axis of propagation of said electrooptic clad waveguide;
• said first and second cladding regions are poled along substantially the same contour of said electric field;
• and said contoured electric field is defined by substantially equivalent x and y components in an x-y plane defined by said x and y axes.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, a second cladding region offset from said z axis in a second direction along said x axis, and first and second control electrodes, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second control electrodes are arranged to enable electrooptic modification of said refractive indices of said first and second cladding regions by creating a contoured electric field in said first and second cladding regions;
• said contoured electric field and said respective directions of polarization in said first and second cladding regions define a Polarization-independent waveguide structure along said primary axis of propagation of said electrooptic clad waveguide;
• said first and second cladding regions are poled along substantially the same contour of said electric field;
• said contoured electric field is defined by x and y components in an x-y plane defined by said x and y axes;
• and
• said contoured electric field is established such that said x and y components in each of said cladding regions define substantially equivalent phase control of respective TE and TM modes of propagation of an optical signal propagating along said primary axis of propagation z.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, a second cladding region offset from said z axis in a second direction along said x axis, and first and second control electrodes, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second control electrodes are arranged to enable electrooptic modification of said refractive indices of said first and second cladding regions by creating a contoured electric field in said first and second cladding regions;
• said contoured electric field and said respective directions of polarization in said first and second cladding regions define a polarization-independent waveguide structure along said primary axis of propagation of said electrooptic clad waveguide;
• said first and second cladding regions are poled along substantially same contour of said electric field;
• an optical signal having respective TIE and TM modes of propagation may pass along said primary axis of propagation z;
• and
• said arrangement of said first and second control electrodes and said polarization of said first and second cladding regions enable substantially equivalent phase modification of said TE and TM modes of said optical signal.

An electrooptic clad waveguide comprising an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, a second cladding region offset from said z axis in a second direction along said x axis, and first and second control electrodes, wherein:

• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said first and second control electrodes are arranged to enable electrooptic modification of said refractive indices of said first and second cladding regions by creating a contoured electric field in said first and second cladding regions;
• said contoured electric field and said respective directions of polarization in said first and second cladding regions define a polarization-independent waveguide structure alone said primary axis of propagation of said electrooptic clad waveguide;
• said first and second cladding regions are poled along substantially the same contour of said electric field;
• and
• said first and second control electrodes cooperate with a dielectric constant medium to create said contoured electric field in said first and second cladding regions.

An integrated optical device comprising an optical input, an optical output, an electrooptic clad waveguide, and first and second control electrodes, wherein:

• said electrooptic clad waveguide is arranged along an optical path defined between said optical input and said optical output;
• said electrooptic clad waveguide is characterized by an optical phase delay φ=2πLncff/λ, where ncff is the effective index of refraction of said waveguide. L is the length over which the phase delay occurs, and λ is the wavelength of light propagating along said optical path;
• said electrooptic clad waveguide comprises an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, and a second cladding region offset from said z axis in a second direction along said x axis;
• said optical waveguide core comprises a substantially non-electrooptic material defining a refractive index n1;
• said first cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises an electrooptic polymer defining a refractive index that is less than n1;
• said waveguide core defines a cross-sectional x axis width that decreases from a region outside of said first and second cladding regions to a region bounded by said first and second cladding regions;
• and
• said first and second control electrodes are ax-ranged to create an electric field in said first and second cladding regions capable of changing said refractive indices of said first and second electrooptic cladding regions without a corresponding change in said refractive index n1of said waveguide core so as to induce a core-independent change in neff and a corresponding change in said optical phase delay φ of said waveguide.

An integrated optical device comprising first and second waveguides arranged to define a Mach-Zehnder interferometer including first and second directional coupling regions, an intermediate coupling region disposed between said first and second directional coupling regions, a set of control electrodes, an optical input, and at least one optical output, wherein:

• at least one of said first and second waveguides comprises an electrooptic clad waveguide comprising a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said electrooptic clad waveguide is disposed between first and second cladding regions in said intermediate coupling region;
• said first cladding region comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said control electrodes are arranged to create an electric field in said first and second cladding regions capable of changing said refractive indices of said first and second electrooptic cladding regions so as to induce a change in an effective index of refraction neff of said electrooptic clad waveguide;
• and
• said control electrodes are arranged such that a quantitative combination of said electric field and said poling in said first cladding region is substantially equivalent to a quantitative combination of said electric field and said poling in said second cladding region, whereby an output intensity Iout at one of said optical outputs is related to an input intensity Iin according to one of the following equations [LeftBracketingBar] I ou ⁢ ⁢ t [RightBracketingBar] 2 = [LeftBracketingBar] I i ⁢ ⁢ n [RightBracketingBar] 2 ⁢ sin 2 ⁡ ( φ 2 ) [LeftBracketingBar] I out [RightBracketingBar] 2 = [LeftBracketingBar] I i ⁢ ⁢ n [RightBracketingBar] 2 ⁢ cos 2 ⁡ ( φ 2 )
• where φ represents optical phase delay resulting from said change in said effective index of refraction neff of said electrooptic clad waveguide.

An integrated optical device comprising first and second electrooptic clad waveguides arranged to define a Mach-Zehnder interferometer including first and second directional coupling regions, an intermediate coupling region disposed between said first and second directional coupling regions, a set of control electrodes, first and second optical inputs, and first and second optical outputs, wherein:

• said first electrooptic clad waveguide comprises a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said first waveguide is disposed between first and second cladding regions of said first waveguide in said intermediate coupling region;
• said first cladding region of said first waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region of said first waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second electrooptic clad waveguide comprises a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said second waveguide is disposed between first and second cladding regions of said second waveguide in said intermediate coupling region;
• said first cladding region of said second waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region of said second waveguide comprises a poled electrooptic polymer defining a refractive index that is less that n1;
• said poling of said first and second cladding regions of said first waveguide is substantially perpendicular to said poling of said first and second cladding regions of said second waveguide;
• and
• said control electrodes are arranged to create an electric field in said first and second cladding regions of said first and second waveguides to induce a change in an effective index of refraction ncff of said first and second waveguides, whereby input optical signals may be directed selectively to separate ones of said optical outputs by controlling said electric field.

An integrated optical device comprising first and second waveguides arranged to define a Mach-Zehnder interferometer including first and second directional coupling regions, an intermediate coupling region disposed between said first and second directional coupling regions, a set of control electrodes, an optical input, and at least one optical output, wherein:

• at least one of said first and second waveguides comprises an electrooptic clad waveguide comprising a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said electrooptic clad waveguide is disposed between first and second cladding regions in said intermediate coupling region;
• said first cladding region comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said control electrodes form a traveling wave stripline and are arranged to create an electric field in said first and second cladding regions capable of changing said refractive indices of said first and second electrooptic cladding regions so as to induce a change in an effective index of refraction ncff of said electrooptic clad waveguide;
• said traveling wave stripline is characterized by a dielectric constant E selected such that an optical signal propagating in said electrooptic clad waveguide propagates at the same velocity as an electrical signal propagating in said traveling wave stripline;
• and
• said control electrodes are arranged such that a quantitative combination of said electric field and said poling in said first cladding region is substantially equivalent to a quantitative combination of said electric field and said poling in said second cladding region, whereby an output intensity Iout at one of said optical outputs is related to an input intensity Iin according to one of the following equations [LeftBracketingBar] I ou ⁢ ⁢ t [RightBracketingBar] 2 = [LeftBracketingBar] I i ⁢ ⁢ n [RightBracketingBar] 2 ⁢ sin 2 ⁡ ( φ 2 ) [LeftBracketingBar] I out [RightBracketingBar] 2 = [LeftBracketingBar] I i ⁢ ⁢ n [RightBracketingBar] 2 ⁢ cos 2 ⁡ ( φ 2 )
• where φ represents optical phase delay resulting from said change in said effective index of refraction ncff of said electrooptic clad waveguide.

An integrated optical device comprising first and second electrooptic clad waveguides of unequal length arranged to define an asymmetric Mach-Zehnder interferometer including first and second directional coupling regions, an intermediate coupling region disposed between said first and second directional coupling regions, a set of control electrodes, an optical input, and first and second optical outputs, wherein:

• said first electrooptic clad waveguide comprises a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said first waveguide is disposed between first and second cladding regions of said first waveguide in said intermediate coupling region;
• said first cladding region of said first waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region of said first waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second electrooptic clad waveguide comprises a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said second waveguide is disposed between first and second cladding regions of said second waveguide in said intermediate coupling region;
• said first cladding region of said second waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region of said second waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said poling of said first and second cladding regions of said first waveguide is substantially perpendicular to said poling of said first and second cladding regions of said second waveguide;
• and
• said control electrodes are arranged to create an electric field in said first and second cladding regions of said first and second waveguides to induce a change in an effective index of refraction ncff of said first and second waveguides, whereby first and second wavelength components of an input optical signal may be directed selectively to separate ones of said optical outputs by controlling said electric field.

An integrated optical device comprising first and second electrooptic clad waveguides arranged to define a directional coupling region., a set of control electrodes, first and second optical inputs, and first and second optical outputs, wherein:

• said first electrooptic clad waveguide comprises a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said first waveguide is disposed between a first outer electrooptic cladding region and an electrooptic gap region in said directional coupling region;
• said first outer cladding region comprises a paled electrooptic polymer defining a refractive index that is less than n1;
• said electrooptic gap region comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second electrooptic clad waveguide comprises a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said second waveguide is disposed between a second outer electrooptic cladding region and said electrooptic gap region in said directional coupling region,
• said second outer cladding region comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said control electrodes are arranged to create an electric field across said outer cladding regions and said electrooptic gap region, whereby an optical signal incident in one of said waveguides may be switched to the other of said waveguides;
• and
• said outer cladding regions are poled perpendicular to said electrooptic gap region.

An optical waveguide comprising an optical input, an optical Output, and a waveguide core, wherein:

• said waveguide core defines a core height dimension h that remains substantially constant between said optical input and said optical output;
• said core width dimension defines an input width w1 at said optical input, an output width w2 at said optical output, an increased-width w0 alone a phase compensating element of said waveguide core, and a decreased-width w3 along a thinned-down portion of said waveguide core;
• said increased-width w0 is greater than said input width:
• said decreased-width w3 is less than said input width:
• said thinned-down portion introduces a first phase shift in an optical signal propagating from said optical input to said optical output;
• said phase compensating element introduces a second phase shift in said optical signal;
• and
• said first phase shift is substantially equal and opposite in magnitude to said second phase shift.

An optical waveguide comprising an optical input, an optical output, and a waveguide core, wherein:

• said waveguide core defines a core height dimension h that remains substantially constant between said optical input and said optical output;
• said core width dimension defines an increased-width w0 along a phase compensating element of said waveguide core, and a decreased-width w3 along a thinned-down portion of said waveguide core;
• said decreased-width w3 is less than said core height dimension h;
• and
• said increased-width w0 is greater than said core height dimension L.

An integrated optical device comprising an optical input, an optical output, and an optically functional clad waveguide, wherein:

• said optically functional clad waveguide is arranged along an optical path defined between said optical input and said optical output;
• said optically functional clad waveguide is characterized by an optical phase delay φ=2πLneff/λ, where neff is the effective index of refraction of said waveguide, L is the length over which the phase delay occurs, and λ is the wavelength of light propagating along said optical path;
• said optically functional clad waveguide comprises an optical waveguide core defining a primary axis of propagation z, a first cladding region offset from said z axis in a first direction along an x axis perpendicular to said z axis, and a second cladding region offset from said z axis in a second direction along said x axis;
• said optical waveguide core comprises an optically non-functional material defining a refractive index n1;
• said first cladding region defines a refractive index that is less than n1;
• said second cladding region defines a refractive index that is less than n1;
• said waveguide core defines a cross-sectional x axis width that decreases from a region outside of said first and second cladding regions to a region bounded by said first and second cladding regions;
• and
• said refractive indices of said first and second cladding regions are arranged to change in response to a control parameter without a corresponding change in said refractive index n1of said waveguide core so as to induce a core-independent change in neff and a corresponding change in said optical phase delay φ of said waveguide.

An integrated optical device comprising first and second waveguides arranged to define a Mach-Zehnder interferometer including first and second directional coupling regions, an intermediate coupling region disposed between said first and second directional coupling regions, a set of control electrodes, an optical input, and at least one optical output, wherein:

• at least one of said first and second waveguides comprises an optically functional electrooptic clad waveguide comprising an optically non-functional optical waveguide core defining a refractive index n1;
• said waveguide core of said clad waveguide is disposed between first and second cladding regions in said intermediate coupling region;
• said first cladding region comprises a poled material defining a refractive index that is less than n1;
• said second cladding region comprises a poled material defining a refractive index that is less than n1;
• said control electrodes are arranged to create an electric field in said first and second cladding regions capable of changing said refractive indices of said first and second cladding regions so as to induce a change in an effective index of refraction neff of said waveguide;
• and
• said control electrodes are arranged such that a quantitative combination of said electric field and said poling in said first cladding region is substantially equivalent to a quantitative combination of said electric field and said poling in said second cladding region, whereby an output intensity Iout at one of said optical outputs is related to an input intensity Iin according to one of the following equations [LeftBracketingBar] I ou ⁢ ⁢ t [RightBracketingBar] 2 = [LeftBracketingBar] I i ⁢ ⁢ n [RightBracketingBar] 2 ⁢ sin 2 ⁡ ( φ 2 ) [LeftBracketingBar] I out [RightBracketingBar] 2 = [LeftBracketingBar] I i ⁢ ⁢ n [RightBracketingBar] 2 ⁢ cos 2 ⁡ ( φ 2 )
• where φ represents optical phase delay resulting from said change in said effective index of refraction neff of said waveguide.

An integrated optical device comprising first and second waveguides arranged to define a Mach-Zehnder interferometer including first and second directional coupling regions, an intermediate coupling region disposed between said first and second directional coupling regions, a set of control electrodes, an optical input, and at least one optical output, wherein:

• said first waveguide comprises an electrooptic clad waveguide comprising a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said first waveguide is disposed between first and second cladding regions in said intermediate coupling region;
• said first cladding region of said first waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region of said first waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said control electrodes are arranged to create an electric field capable of changing said refractive indices of said first and second electrooptic cladding regions of said first waveguide;
• said second waveguide comprises an electrooptic clad waveguide comprising a substantially non-electrooptic optical waveguide core defining a refractive index n1;
• said waveguide core of said second waveguide is disposed between first and second cladding regions in said intermediate coupling region;
• said first cladding region of said second waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said second cladding region of said second waveguide comprises a poled electrooptic polymer defining a refractive index that is less than n1;
• said control electrodes are arranged to create an electric field capable of changing said refractive indices of said first and second electrooptic cladding regions of said second waveguide;
• and a poling of said first and second cladding regions of said first waveguide is substantially perpendicular to a poling of said first and second cladding regions of said second waveguide such that each waveguide is configured to modulate a selected polarization more than another.