Quantum system with an optical cavity and optical router
In an example, the present invention provides a quantum communication system. The system has a light source configured to generate a pulse of light and a plurality of optical cavities. In an example, each of the optical cavities has at least a pair of optical mirrors to form a cavity. In an example, each cavity has a plurality of qubits comprising a laser coolable atom. Each cavity has an interconnect coupled to the cavity. In an example, the system has an optical router coupled to the light source coupled to each of the cavities through the interconnect. In an example, the optical router is configured to transmit the pulse of light to any one of the plurality of optical cavities or receive a reflected pulse of light from any one of the plurality of optical cavities and transmit the reflected pulse.
1 . A quantum communication system, the system comprising:
a light source configured to generate a pulse of light;
a plurality of optical cavities, each of the optical cavities having:
at least a pair of optical mirrors each characterized by a mirror reflectivity >99% and having reflecting surfaces facing each other to form a cavity, the cavity having a length ranging from 1 micrometer to 1 centimeter; and
a plurality of qubits comprising a laser coolable atom, ion, nitrogen vacancy center, or silicon color center, such that a number of the qubits range from two to 100,000;
an interconnect coupled to each cavity;
an optical router coupled to the light source and coupled to each of the cavities through the interconnect, the optical router configured to transmit the pulse of light to any one of the plurality of optical cavities and receive a reflected pulse of light from any one of the plurality of optical cavities, and subsequently transmit the reflected pulse; and
a beam splitter coupled to the optical router to receive the reflected light and configured to output the reflected light to an output port.
2 . The system of claim 1 wherein the beam splitter is configured to receive a generated pulse of light to displace a phase space distribution of the pulse of light generated by the light source.
3 . The system of claim 1 wherein each of the plurality of optical cavities further comprises a plurality of electrical coil pairs to control a magnetic field and magnetic field gradient at locations of the qubits and a detection system operably coupled to a cavity region configured to collect one or more fluorescence photons to be sent to a camera or a detector with a quantum efficiency of 0.1 or higher.
4 . The system of claim 3 further comprising a computing system comprising an information processing unit configured to process a recorded qubit state information captured from the camera or the detector and configured to identify a quantum state of the qubits.
5 . The system of claim 4 wherein the computing system is configured to decode using the information processing unit a quantum error information from measurement results.
6 . The system of claim 1 wherein the pair of optical mirrors is selected from a free-space bulk mirror, a fiber-based mirror, or a fiber Bragg grating mirrors.
7 . The system of claim 1 wherein one or more qubits are coupled to a cavity mode between the two free-space bulk mirrors or a fiber-based mirrors.
8 . The system of claim 1 wherein one or more qubits are evanescently coupled to a cavity mode between the two optical mirrors at a nanofiber region, the nanofiber region configured from a portion of a fiber optic cable and coupled between a first fiber Bragg grating mirror and a second fiber Bragg grating mirror, the nanofiber region having a transmission of ≥99%, the nanofiber region having a diameter ranging from 300 nanometers to 1.5 micrometer, and the nanofiber region ranging from 10 micrometers to 10 centimeters in length.
9 . The system of claim 1 wherein the interconnect is coupled to one or more of a single-photon generator, a photon detector, a network comprising of one or more optical cavities each of which is identical, a single-photon source, a semiconductor single-photon emitter, an optical router, an optical switch, circulators, a polarization beam splitter, a coherent light source, a squeezed light source, or an optical homodyne and heterodyne detector.
10 . The system of claim 1 further comprising a communication input port coupled to the optical router.
11 . The system of claim 1 further comprising a communication output port coupled to a feedforward displacement operation such that a communication output light pulse represents a same encoded state of a light pulse received at the communication input port with a reduced error.
12 . A quantum communication system, the system comprising:
a light source configured to generate a pulse of light;
a plurality of optical cavities, each of the optical cavities having:
at least a pair of optical mirrors each characterized by a mirror reflectivity >99% and having reflecting surfaces facing each other to form a cavity, the cavity having a length ranging from 1 micrometer to 1 centimeter; and
a plurality of qubits comprising a laser coolable atom, ion, nitrogen vacancy center, or silicon color center, such that a number of the qubits range from two to 100,000;
an interconnect coupled to each cavity;
an optical router coupled to the light source and coupled to each of the cavities through the interconnect, the optical router configured to transmit the pulse of light to any one of the plurality of optical cavities and receive a reflected pulse of light from any one of the plurality of optical cavities, and subsequently transmit the reflected pulse;
at least one input fiber coupled to the optical router; and
at least one output fiber coupled to the optical router.
13 . The system of claim 12 further comprising a single photon detector device coupled to the optical router.
14 . The system of claim 12 wherein the optical interconnect is coupled to one or more of a single-photon generator, a photon detector, a network comprising of one or more optical cavities each of which is identical, a single-photon source, a semiconductor single-photon emitter, an optical router, an optical switch, circulators, a polarization beam splitter, a coherent light source, a squeezed light source, or an optical homodyne and heterodyne detector.
15 . The system claim 12 wherein the system is characterized as a repeater cell system configured to encode one or more photons into an entangled state such that the entangled state comprises a logical state such that a photon loss can be detected and corrected to preserve a logical qudit information.
16 . The system of claim 12 wherein the system is configured to entangle a state of one or more encoded photons with one or more states of the qubits in the optical cavities.
17 . The system of claim 12 wherein the system is configured to relay quantum information transmitted using one or more photons to a neighboring repeater cell system by an entanglement swapping operation or measurement and re-encoding of an incoming photonic encoded qudit information.