Device and method for variable attenuation of an optical channel

An optical attenuator device selectively operable in an actuated state and a non-actuated state, comprising;

• a core;
• a lower cladding layer downwardly bounding said core;
• a substrate affixed to said lower cladding layer;
• an adhesion layer interposed between said substrate and said lower cladding layer, said adhesion layer has having a refractive index which is less than the refractive index of said substrate and greater than or equal to the refractive index of said lower cladding layer;
• a first upper cladding sublayer upwardly and laterally bounding said core, wherein said core, said lower cladding layer and said first upper cladding sublayer have matched thermo-optic coefficients;
• a second upper cladding sublayer upwardly adjacent to said first upper cladding sublayer and having a refractive index substantially lower than the refractive index of said first upper cladding sublayer;
• and
• a resistive heater positioned above said core, said resistive heater being configured to generate a thermal gradient within said core, when said attenuator device is in the actuated state, such that the refractive index of a portion of said core is decreased below the refractive index of a portion of said lower cladding layer located downwardly adjacent to said core, causing a portion of the optical energy traveling along said core to be deflected downwardly and extracted from said core.

An optical attenuator device selectively operable in an actuated state and a non-actuated state, comprising:

• a core;
• a lower cladding layer downwardly bounding said core;
• a first upper cladding sublayer upwardly and laterally bounding said core, wherein said core, said lower cladding layer and said first upper cladding sublayer have matched thermo-optic coefficients;
• a second upper cladding sublayer upwardly adjacent to said first upper cladding sublayer and having a refractive index substantially lower than the refractive index of said first upper cladding sublayer;
• and
• a resistive heater positioned above said core, said resistive heater being configured to and being capable of generating an average vertical thermal gradient within said core of at least 0.53° C./μm, when said attenuator device is in the actuated state, such that the refractive index of a portion of said core is decreased below the refractive index of a portion of said lower cladding layer located downwardly adjacent to said core, causing a portion of the optical energy traveling along said core to be deflected downwardly and extracted from said core.

An optical attenuator device selectively operable in an actuated state and a non-actuated state, comprising:

• a core;
• a lower cladding layer downwardly bounding said core;
• a first upper cladding sublayer upwardly and laterally bounding said core, wherein said core, said lower cladding layer and said first upper cladding sublayer have matched thermo-optic coefficients;
• a second upper cladding sublayer upwardly adjacent to said first upper cladding sublayer and having refractive index substantially lower than the refractive index of said first upper cladding sublayer;
• and
• a resistive heater positioned above said core, said resistive heater being configured to and being capable of generating an average vertical thermal gradient within said core of at least 0.67° C./μm, when said attenuator device is in the actuated state, such that the refractive index of a portion of said core is decreased below the refractive index of a portion of said lower cladding layer located downwardly adjacent to said core, causing a portion of the optical energy traveling along said core to be deflected downwardly and extracted from said core.

An optical attenuator device selectively operable in an actuated state and a non-actuated state, comprising:

• a core;
• a lower cladding layer downwardly bounding said core;
• a first upper cladding sublayer upwardly and laterally bounding said core, wherein said core, said lower cladding layer and said first upper cladding sublayer have matched thermo-optic coefficients;
• a second upper cladding sublayer upwardly adjacent to said first upper cladding sublayer and having a refractive index substantially lower than the refractive index of said first upper cladding sublayer;
• and
• a resistive heater positioned above said core but no more than 5 μm above an upper boundary of said core, said resistive heater being configured to generate a thermal gradient within said core, when said attenuator device is in the actuated state, such that the refractive index of a portion of said core is decreased below the refractive index of a portion of said lower cladding layer located downwardly adjacent to said core, causing a portion of the optical energy traveling along said core to be deflected downwardly and extracted from said core.