Described is a method of setting up a plurality of quantum communications links, forming a quantum network providing provably secure communications and internet services over intercontinental distances without requiring direct line of sight communication or the intermediate use of the entanglement resource of satellites. Also described is a quantum communicator device for use in this method. Two or more quantum memory units are disposed at a first location, an entangled link is set up between at least two of the quantum memory units, at least one of the quantum memory units sharing in the entangled link is physically transported to a second location. The quantum communicator device comprises communications nodes, an optical interface to set up entanglement to other devices and storage nodes, each node in the form of a quantum memory unit capable of storing quantum information for a desired length of time, i.e. weeks or longer.

Aspects of the subject disclosure may include a communication system including a full duplex transceiver is configured to transmit and receive electromagnetic wave signals simultaneously over a transmission medium; a processing system including a processor; and a memory that stores executable instructions that, when executed by the processing system, facilitates the performance of operations, including: transmitting, via the full duplex transceiver, electromagnetic wave signals that convey a plurality of data frames, wherein the electromagnetic wave signals propagate along the transmission medium to another transceiver, wherein the electromagnetic wave signals propagate along the transmission medium without requiring an electrical return path; monitoring, via the full duplex transceiver, the transmission medium for an interference; identifying, via the full duplex transceiver, one or more data frames of the plurality of data frames that were transmitted during a period of the interference; and retransmitting, via the full duplex transceiver, the one or more data frames. Other embodiments are disclosed.

An apparatus includes a horn having a horn body including at least one horn sidewall defining a first opening that tapers down to a second opening in a direction of elongation and a port that is tubular and dimensionally uniform transverse to the direction of elongation and extends in the direction of elongation from a first port end that is in communication with the second opening to a second port end that defines an external opening. A dielectric rod includes a rod length extending between a first rod end and a second rod end with the first rod end extending through the external opening of the second port end and into the port cavity such that the first rod end is in a spaced apart relationship from the port sidewall along the light path.

An apparatus includes a horn having a horn body including at least one horn sidewall defining a first opening that tapers down to a second opening in a direction of elongation and a port that is tubular and dimensionally uniform transverse to the direction of elongation and extends in the direction of elongation from a first port end that is in communication with the second opening to a second port end that defines an external opening. A dielectric rod includes a rod length extending between a first rod end and a second rod end with the first rod end extending through the external opening of the second port end and into the port cavity such that the first rod end is in a spaced apart relationship from the port sidewall along the light path.

Optical switch and modulator devices are described, usable for Terahertz data communication rates. The device comprising an optically transmissive substrate configured for propagating electromagnetic radiation therethrough and a metamaterial arrangement optically coupled to said substrate. The metamaterial arrangement comprises at least one layer of metamaterial particles optically coupled to at least some portion of said optically transmissive substrate, and at least one nanomesh layer made of at least one electrically conducting material placed over at least some portion of the at least one metamaterial layer. The at least one nanomesh layer configured to discharge electrons into the at least one metamaterial layer responsive to electromagnetic or electric signals applied to the metamaterial arrangement, and the at least one metamaterial layer configured to change from an optically opaque state into an optically transparent state upon receiving the discharged electrons, to thereby at least partially alter electromagnetic radiation passing through the substrate.

Optical switch and modulator devices are described, usable for Terahertz data communication rates. The device comprising an optically transmissive substrate configured for propagating electromagnetic radiation therethrough and a metamaterial arrangement optically coupled to said substrate. The metamaterial arrangement comprises at least one layer of metamaterial particles optically coupled to at least some portion of said optically transmissive substrate, and at least one nanomesh layer made of at least one electrically conducting material placed over at least some portion of the at least one metamaterial layer. The at least one nanomesh layer configured to discharge electrons into the at least one metamaterial layer responsive to electromagnetic or electric signals applied to the metamaterial arrangement, and the at least one metamaterial layer configured to change from an optically opaque state into an optically transparent state upon receiving the discharged electrons, to thereby at least partially alter electromagnetic radiation passing through the substrate.

A system includes a transmission unit, a reception unit, and a lens unit and is placed in a passage, wherein in a case where a first plane that intersects a forward direction of the passage and is a surface of an object, and a second plane that intersects the forward direction of the passage, includes the lens unit, and is at a position different from a position of the first plane are set, a first area to which a terahertz wave from the transmission unit reflected from the first plane is emitted and the lens unit are disposed at positions different from each other on the second plane.

A system includes a transmission unit, a reception unit, and a lens unit and is placed in a passage, wherein in a case where a first plane that intersects a forward direction of the passage and is a surface of an object, and a second plane that intersects the forward direction of the passage, includes the lens unit, and is at a position different from a position of the first plane are set, a first area to which a terahertz wave from the transmission unit reflected from the first plane is emitted and the lens unit are disposed at positions different from each other on the second plane.

A system uses pulsed lasers to enhance a signal propagation path in a telecommunications network. The system can estimate a signal propagation path, which varies based on a current location of a mobile device relative to a base station. The system can detect a propagation loss due to a condition of a propagation medium including the signal propagation path and determine whether the mobile device is in Line-of-Sight (LOS) of a laser emitter. In response to detection of the propagation loss, the laser emitter can emit a pulsed laser that can enhance signal propagation by mitigating the propagation loss on the signal propagation path. The pulsed laser has a propagation path overlapping the signal propagation path when the mobile device is in LOS of the laser emitter, which is mounted on the base station.

A high-electron mobility transistor (HEMT) array terahertz wave modulator loaded in a waveguide is provided, which belongs to the technical field of electromagnetic functional devices and focuses on fast dynamic functional devices in the terahertz band. The device comprises a waveguide cavity and a modulation chip. The modulation chip comprises a semiconductor material substrate, a heterostructure material epitaxial layer, an artificial microstructure, and a socket circuit. The applied voltage controls the distribution change of the two-dimensional electron gas in the HEMT, which in turn controls the resonance mode conversion in the artificial microstructure, thereby control the transmission of electromagnetic waves in the waveguide. The modulator has a modulation depth of up to 96% and a modulation rate above 2 GHz.