Wide bandwidth, low loss photonic bandgap fibers

Abstract

Various embodiments include photonic bandgap fibers (PBGF). Some PBGF embodiments have a hollow core (HC) and may have a square lattice (SQL). In various embodiments, SQL PBGF can have a cladding region including 2-10 layers of air-holes. In various embodiments, an HC SQL PBGF can be configured to provide a relative wavelength transmission window Δλ/λc larger than about 0.35 and a minimum transmission loss in a range from about 70 dB/km to about 0.1 dB/km. In some embodiments, the HC SQL PBGF can be a polarization maintaining fiber. Methods of fabricating PBGF are also disclosed along with some examples of fabricated fibers. Various applications of PBGF are also described.

What is claimed is: 
     
         1 . A photonic bandgap fiber (PBGF) for propagating light having a wavelength, λ, said fiber comprising:
 a core; and 
 a cladding disposed about said core, said cladding comprising a plurality of regions, at least one region having a dimension, Λ, and configured such that the cladding at least partially surrounds a hole having a hole dimension, D, 
 wherein said plurality of regions are arranged as a rectangular lattice, and 
 wherein said PBGF is configured such that a relative wavelength transmission window Δλ/λc is larger than about 0.35. 
 
     
     
         2 . The photonic bandgap fiber of  claim 1 , wherein said rectangular lattice comprises a square lattice. 
     
     
         3 . The photonic bandgap fiber of  claim 1 , wherein a dimension of said core is in a range from about 10 μm to about 100 μm. 
     
     
         4 . The photonic bandgap fiber according to  claim 1 , wherein Δλ/λc is in the range from about 0.35 to about 0.85. 
     
     
         5 . The photonic bandgap fiber of  claim 1 , wherein:
 said cladding comprises webs and nodes of said rectangular lattice such that at least a portion of said webs have a dimension, d 2 , and are configured as higher aspect ratio cladding material portions, and   a portion of the webs are connected to said nodes, at least a portion of said nodes having a dimension, d 1 , and configured as lower aspect ratio cladding material portions.   
     
     
         6 . The photonic bandgap fiber of  claim 5 , wherein d 2 /Λ is in a range from about 0.01 to about 0.1, and d 1 /Λ is in a range from about 0.1 to about 0.5. 
     
     
         7 . The photonic bandgap fiber of  claim 5 , wherein d 2 /d 1  is less than approximately 0.15, and d 1 /Λ is in a range from about 0.05 to about 0.3. 
     
     
         8 . The photonic bandgap fiber of  claim 5 , wherein the webs have a second dimension d 3 , such that a ratio of d 3  to d 2  is at least approximately 5:1 and less than approximately 25:1. 
     
     
         9 . The photonic bandgap fiber of  claim 1 , wherein said rectangular lattice comprises 2 to 5 layers of cladding regions. 
     
     
         10 . The photonic bandgap fiber of  claim 1 , wherein said PBGF is configured to be polarization maintaining. 
     
     
         11 . The photonic bandgap fiber of  claim 1 , wherein the PBGF has a minimum transmission loss in a range from about 70 dB/km to about 0.1 dB/km. 
     
     
         12 . The photonic bandgap fiber of  claim 1 , wherein a hole filling fraction of the cladding exceeds about 80% and is up to about 95%. 
     
     
         13 . The photonic bandgap fiber of  claim 1 , wherein the PBGF has a relative bandgap greater than approximately 0.35 and less than approximately 0.80. 
     
     
         14 . The photonic bandgap fiber of  claim 1 , wherein dispersion of said PBGF is tailored to provide compression for said propagating light. 
     
     
         15 . A system for telecommunications comprising the PBGF according to  claim 1 . 
     
     
         16 . A system for gas measurement comprising the PBGF according to  claim 1 . 
     
     
         17 . A system for delivery of high peak power pulses comprising the PBGF according to  claim 1 . 
     
     
         18 . A system for laser pulse shaping comprising the PBGF according to  claim 1 . 
     
     
         19 . A system for sensor applications comprising the PBGF according to  claim 1 . 
     
     
         20 . A pulse compressor comprising the PBGF according to  claim 1 . 
     
     
         21 . The photonic bandgap fiber of  claim 1 , wherein the core comprises a hollow region. 
     
     
         22 . A method of fabricating the photonic bandgap fiber of  claim 21 , comprising:
 constructing a preform comprising capillaries and rods stacked to form a rectangular lattice, said rods comprising an optical material, said preform having webs having a web dimension and nodes having a node dimension;   drawing said preform into the photonic bandgap fiber of  claim 12 ; and   controlling pressure in said hollow region and said cladding during said drawing, said pressure in said hollow region being different from said pressure in said cladding, said controlling narrowing the web dimension and substantially limiting changes in the node dimension.   
     
     
         23 . The method of  claim 22 , wherein said pressure in said cladding is from about 0.5 to about 2.5 psi and said pressure in said hollow region is from about of 0.2 to about 2 psi, and said pressure in said cladding pressure exceeds said pressure in said hollow region. 
     
     
         24 . The method of  claim 22 , wherein said controlling provides that a relative reduction in the node dimension is substantially less than a relative reduction in the web dimension. 
     
     
         25 . The method of  claim 22 , wherein said lattice of said preform has four-fold symmetry, and said method further comprises transforming said four-fold symmetry of said lattice into two-fold symmetry by deforming said hollow region and said cladding during said drawing, thereby introducing birefringence into said PBGF.