Anti-resonant hollow-core fibers featuring support structures
An optical fiber may include a cladding structure extending along a fiber length providing a hollow interior fiber region, and anti-resonant (AR) elements formed as walled structures with walls extending along the fiber length. At least one of the AR elements surrounds an interior region and further includes one or more support structures in the interior region and formed as at least a portion of at least one of the walls, where the one or more support structures have a non-uniform thickness profile, and where the plurality AR elements is configured to guide light along the fiber length in a central portion of the hollow interior fiber region based on optical anti-resonance.
1. An optical fiber comprising:
a cladding structure extending along a fiber length providing a hollow interior fiber region; and
a plurality of anti-resonant (AR) elements formed as walled structures with walls extending along the fiber length, wherein the plurality of AR elements is configured to guide light along the fiber length in a central portion of the hollow interior fiber region based on optical anti-resonance, wherein the plurality of AR elements includes at least one nested set of AR elements comprising:
a first AR element formed as a wall extending along the fiber length and located entirely within the hollow interior fiber region, wherein the wall of the first AR element, in a cross-sectional plane orthogonal to the fiber length, fully surrounds an interior region and further has a non-uniform thickness profile between the first interior region and an outer perimeter of the first AR element, wherein the non-uniform thickness profile forms a support structure with a solid shape in the cross-sectional plane; and
a second AR element located within the interior region of the first AR element and exclusively in contact with the support structure.
2. The optical fiber of claim 1 , wherein a fill factor defined as a ratio of an area of the walls of the first AR element in the cross-sectional plane to an area of the first AR element bounded by an outer face in the cross-sectional plane is at least 20%.
3. The optical fiber of claim 1 , wherein the second AR element is connected to the support structure at one or more contact points, wherein the non-uniform thickness profile of the first AR element is selected to provide selected separation distances between the one or more contact points and an outer face of the first AR element.
4. The optical fiber of claim 3 , wherein the second AR element is connected to the support structure at two or more contact points.
5. The optical fiber of claim 1 , wherein the support structure is porous.
6. The optical fiber of claim 1 , wherein the support structure is shaped as at least one of an ellipse or a circle in the cross-sectional plane.
7. The optical fiber of claim 1 , wherein the support structure is shaped as at least one of a truncated ellipse or a truncated circle in a cross-sectional plane.
8. The optical fiber of claim 1 , wherein the at least one set of nested AR elements further comprises:
one or more additional second AR elements located within an interior region of the first AR element bounded at least in part by the walls of the second AR element and attached to the support structure.
9. The optical fiber of claim 1 , wherein the at least one set of nested AR elements further comprises:
a third AR element of the plurality of AR elements located within an interior region of the second AR element bounded at least in part by the walls of the second AR element.
10. The optical fiber of claim 9 , wherein the third AR element is connected to one or more additional support structures.
11. The optical fiber of claim 1 , wherein the plurality of AR elements is divided into two or more sets of AR elements, wherein each of the two or more sets of AR elements is connected to at least one of the cladding structure or one or more additional support structures, wherein the two or more sets of AR elements comprise:
a first set of AR elements having a first design; and
a second set of AR elements having a second design.
12. An optical fiber comprising:
a cladding structure extending along a fiber length providing a hollow interior fiber region; and
one or more nested sets of anti-resonant (AR) elements formed as walled structures with walls extending along the fiber length, wherein a particular one of the one or more nested sets of AR elements comprises:
a first AR element formed as a wall extending along the fiber length and located entirely within the hollow interior fiber region, wherein the wall of the first AR element, in a cross-sectional plane orthogonal to the fiber length, fully surrounds an interior region; and
a second AR element within the interior region of the first AR element, wherein the second AR element is exclusively coupled with a slab support structure and positioned with the interior region by the slab support structure, wherein the slab support structure has a non-uniform thickness profile, wherein the one or more nested sets of AR elements are configured to guide light along the fiber length in a central portion of the hollow interior fiber region based on optical anti-resonance.
13. The optical fiber of claim 12 , wherein the slab support structure is formed from the walls of the first AR element, wherein the walls of the first AR element have the non-uniform thickness profile in a cross-sectional plane defining a shape of the slab support structure, wherein the cross-sectional plane is orthogonal to a direction along the fiber length.
14. The optical fiber of claim 13 , wherein a fill factor defined as a ratio of an area of the walls of the first AR element in the cross-sectional plane to an area of the first AR element bounded by an outer face in the cross-sectional plane is at least 20%.
15. The optical fiber of claim 12 , wherein the second AR element is connected to the slab support structure at one or more contact points, wherein the non-uniform thickness profile of the slab support structure is selected to provide selected separation distances between the one or more contact points and an outer face of the first AR element.
16. The optical fiber of claim 15 , wherein the second AR element is connected to the slab support structure at two or more contact points.
17. The optical fiber of claim 12 , wherein the slab support structure is porous.