Concentric fiber for space-division multiplexed optical communications and method of use

An optical communications system, comprising:

• a first transmitter unit to generate a first optical information data signal;
• a second transmitter unit to generate a second optical information data signal;
• an optical fiber comprising:
• a relatively high refractive index optical core region formed of material having a first refractive index;
• a first low index region surrounding the optical core region and formed from a material having a second refractive index lower than the first refractive index;
• a first high index ring region surrounding the first low index region and formed of a material having a third refractive index higher than the second refractive index;
• and
• a second low index region surrounding the first high index ring region and formed from a material having a fourth refractive index lower than the third refractive index;
• wherein the optical core region supports propagation of light along at least a first radial mode associated with the optical core region and the first high index ring region supports propagation of light along at least a second radial mode associated with the first high index ring region, the second radial mode being different from the first radial mode;
• a first receiver unit;
• and
• a second receiver unit;
• wherein the first optical information data signal from the first transmitter unit is transmitted through the relatively high refractive index core region of the optical fiber to the first receiver unit and the second optical information data signal from the second transmitter unit is transmitted through the first high index ring region to the second receiver unit.