Method of Manufacturing Nanofiber Cavity for Quantum Computing and Device

A method of manufacturing a polarization-degenerate fiber Bragg grating nanofiber cavity for quantum computing, the method comprising:

• providing a fiber optical cable region comprising a first end, a second end, and a nanofiber region between the first end and the second end;
• transmitting electromagnetic radiation characterized by a wavelength of 150 nm to 400 nm and longer through phase shift mask to diffract the electromagnetic radiation to form an interference pattern to be illuminated onto a core of a first end of the fiber optical cable region;
• causing a formation of a first fiber Bragg grating onto the core of a first end of a fiber optical cable region by changing a refractive index of the core of fiber optical cable region using the electromagnetic radiation without rotating the fiber to create an additional spatial region of the fiber optical cable region such that first fiber Bragg granting has a plurality of azimuthally anisotropic patterns of a plurality of refractive index modulations around the core of the fiber optical cable region and along a longitudinal region normal to a cross-section of the fiber optical cable region;
• rotating the fiber optical cable region about an axis defined along a length of the fiber optical cable region by 90 degrees in angle;
• forming a second fiber Bragg grating onto a core of a second end of the fiber optical cable region without rotating the fiber such that the first fiber Bragg grating and the second fiber Bragg grating are characterized by respective transverse anisotropies of refractive index modulations shifted by 90 degrees in angle, causing a polarization degenerate cavity from a cancellation of transverse anisotropy.

A quantum computer and repeater cell system, the system comprising:

• a fiber optical cable region having a first end region and a second end region, the first end region having a first end, and the second end region having a second end, the fiber optical cable region comprising silicon dioxide material with dopant material entity distributed inside of a core region;
• a first fiber Bragg Grating comprising a plurality of first patterns on the first end region, configured 360 degrees around a periphery of the first end region, and extending laterally along a length of the first end region;
• a second fiber Bragg Grating comprising a plurality of second patterns on the second end region, configured 360 degrees around a periphery of the second end region, and extending laterally along a length of the second end region;
• a nanofiber region configured from a center portion of the fiber optic cable and coupled between the first end region and the second end region, the nanofiber region having a transmission of 95% and greater, the nanofiber region having a diameter ranging from 300 nanometer to 1.5 micrometer, the nanofiber region ranging from 10 micrometer to 10 centimeter in length;
• a first taper region configured from a first portion of the nanofiber region within a vicinity of the first fiber Bragg Grating;
• a second taper region configured from a second portion of the nanofiber region within a vicinity of the second fiber Bragg Grating;
• a cavity formed between the first fiber Bragg Grating and the second fiber Bragg Gratings including the taper regions and the nanofiber region;
• a plurality of atoms comprising an alkali metal atom, an alkaline-earth metal, an alkaline-earth-like atom or other laser coolable atoms such that a number of the atoms range from one to 100,000 and are evanescently coupled to the nanofiber region between the first fiber Bragg grating and the second fiber Bragg grating.