47 results about "Quantum teleportation" patented technology

Techniques for high fidelity quantum teleportation include receiving an input photon representing a qubit. Ancilla photons are generated in a particular ancilla quantum state chosen to reduce a rate of error below a threshold error rate. The ancilla and the input photon are combined to populate output channels. A number of photons representing logical value 1 are measured in a subset of the output channels. A particular output channel is determined based on the measured number of photons. A teleported photon is obtained at the particular output channel with an error rate below the threshold error rate. These techniques allow the ancilla quantum state to be chosen to minimize the error despite the presence of losses and noise. Quantum logic operations are performed by teleporting two input qubits with the quantum state of the ancilla chosen to produce the desired logical result and reduce the error.

The use of quantum-mechanically entangled photons for monitoring the integrity of a physical border or a communication link is described. The no-cloning principle of quantum information science is used as protection against an intruder's ability to spoof a sensor receiver using a ‘classical’ intercept-resend attack. Correlated measurement outcomes from polarization-entangled photons are used to protect against quantum intercept-resend attacks, i.e., attacks using quantum teleportation.

The invention belongs to the technical field of safety communication, and discloses a controlled quantum safe and direct communication method and system for preventing tampering. A receiving end is controlled to obtain secret information of a sending end, and the sending end sends SC* to a control end; the control end disorganizes photons in SC*; then the control end sends rearranged SC* to the receiving end; if the control end does not tell the accurate sequence of the photons to the receiving end, the receiving end cannot resume SC and decrypt the secret information; the control end cannot know the secret information encrypted through K(k1, k2, ..., kN). The premise that a controller is honest is not needed; even under the condition that the controller is dishonest, the proposed protocolis still safe, and any tampering of the secret information can be easily found. By means of the controlled quantum safe direct communication method and system for preventing tampering, attack of fakephotons based on quantum teleportation can be resisted, and meanwhile, identities of two participants, namely, the sender and the receiver, can also be verified.

A method and apparatus for sending encrypted data across a node in a communications network. In one illustrative embodiment, an apparatus comprises a first communicator, a second communicator, and a number of nodes. The first communicator is configured to encrypt unencrypted data to form the encrypted data using a first quantum key distributor. The second communicator is configured to decrypt the encrypted data using a second quantum key distributor. The number of nodes is configured to receive the encrypted data sent from the first communicator and send the encrypted data to the second communicator using quantum teleportation. The encrypted data remains encrypted as the encrypted data passes through each of the number of nodes.

The invention provides an opportunistic quantum network coding method. The opportunistic quantum network coding method is characterized by being designed by giving full play to the characteristics of quantum teleportation, specific classical information is characterized by means of quantum states and transferred through a quantum teleportation method, opportunistic monitoring is achieved through classical channels, and opportunistic characteristics of quantum network coding are achieved; the method includes ten steps. According to the opportunistic quantum network coding method, the classical opportunistic network coding thought is applied to quantum network coding, the absolute security of communication is guaranteed by means of the quantum channels, and thus by means of the character that the classical channels can be monitored, quantum network coding with opportunistic characteristics is achieved; as a result, the security of quantum information transmission in a quantum network coding model is enhanced, and the transmission performance of the quantum network is further improved beneficially.

The invention discloses a node trust-based quantum trust assessment method, including modeling of a quantum trust model and a method for quantum trust assessment. Compared with the prior art, the method uses a trust node-based credible quantum relay network as a research object, introduces trust management into a quantum communication network, uses assessment of a trust value of a node as a basis to build a safe and credible quantum communication network, and uses the trust value as a basis for judging whether users in the quantum communication network are credible; by means of unique characteristics of a quantum entanglement effect and quantum teleportation, the node trust-based quantum trust assessment method is researched and proposed, and the idea and the process of quantum trust assessment are explained in detail; and finally feasibility, reasonability and safety of the node trust-based quantum trust assessment method proposed by the invention are analyzed, thereby providing a valuable new idea and new method for building a safe and credible quantum communication network.

The invention discloses a quantum network coding method based on quantum discord. Characteristics of the quantum discord are brought into full play, entanglement distribution based on the separated state is combined, and the quantum network coding method based on the quantum discard is designed, thus the quantum resource consumption of the entanglement distribution is reduced, and the robustness and the throughput of a communication network are improved. Compared with the prior art, the quantum network coding method based on the quantum discard provided by the invention has the following advantages: (1), the quantum discard is adopted as a measure of quantum correlation to perform the entanglement distribution from the perspective of taking the quantum correlation as a communication resource, thereby reducing the quantum resource consumption of the entanglement distribution and improving the robustness and the throughput of the communication network; and (2), the quantum network codingmethod is designed by adopting the entanglement distribution based on the separated state, no quantum entanglement is involved in an entanglement establishment process, and an entangled particle pairis generated between a source node and a destination node only at the end, so that the advantages of the quantum invisible transmission state in the aspect of information transmission are fully exerted.

The invention discloses a channel multiplexing method based on a 5-bit brown state. The method comprises three parts consisting of a channel multiplexing method in which quantum teleportation and remote state preparation coexist, a channel multiplexing method in which quantum teleportation and quantum dense coding coexist, and a channel multiplexing method in which remote state preparation and quantum dense coding coexist. According to the channel multiplexing method provided by the invention, quantum information can be simultaneously sent and received by two parties of communication, and thequantum information exchange modes are effectively enriched.

The invention belongs to the technical field of quantum communication, and discloses a quantum wireless mesh network routing method and architecture based on entanglement exchange. The method comprises the following steps: taking a comprehensive weight value of node hops and round-trip time parameters in a wireless quantum mesh network as an overhead value of a route, enabling each node to be accessed to the network step by step by using a minimum spanning tree method, and constructing a classical channel in the network; then preparing and distributing entangled particles by a part of nodes inthe network, and performing quantum entanglement exchange and measurement by the other part of nodes to construct a quantum channel; and finally, carrying out quantum information transmission betweenthe source node and the destination node through a quantum stealth state transfer method. According to the method, the wireless quantum mesh network with a complex structure can be logically regardedas a tree-shaped ring-free network topology, so that the generation of network storms is avoided; a ''pairwise combination'' scheme is proposed to establish a quantum channel between a source node and a destination node.

The invention discloses an adaptive RIP routing selection protocol based on quantum teleportation. Efficient, safe and rapid update of routing information in an autonomous system can be achieved, and consumption of entanglement resources can also be reduced as much as possible; a RIP message transmitted by a classical RIP protocol during an information exchange process is subjected to data transmission in a plaintext manner, so that security of the exchanged routing information cannot be ensured; the RIP message is still able to be eavesdropped, tampered and counterfeited; in order to further improve security of exchange of the RIP protocol routing information, the adaptive RIP routing selection protocol based on quantum teleportation provided by the invention provided by the invention introduces a quantum communication technology into a routing selection protocol RIP, and thus security transmission of the routing information is achieved.

The invention discloses a controllable OAM quantum invisible state transfer system based on a W state. the system comprises an Alice sending end and a Bob receiving end. Alice comprises a mixed entanglement unit, an entanglement exchange unit, a Path analysis unit and an SAM analysis unit. the Bob comprises an OAM analysis unit. The Entanglement exchange unit is used for Performing entanglement exchange on the SAM- OAM entangled photon pair, SAM- Path entangled photon pair and SAM-SAM entanglement photon pairs to obtain two W states which are equal in probability and symmetrical to each other,and randomly selecting one W state as a quantum channel; The OAM analysis unit is used for OAM analysis, and Alice can remotely control OAM generation of Bob photons through electric field tuning. The method is an open type target invisible transmission state, an asymmetric light quantum network can be formed, remote control, high-dimensional, expandable and safer quantum invisible transmission state can be realized, and the method has a great application prospect.

The invention discloses an optimal controlled quantum stealth state transfer method with an adjustable threshold value for any unknown n particles. The invention discloses an optimal controlled quantum stealth state transfer method for any unknown n particles with an adjustable threshold value. The method is characterized by comprising the following steps that: a central service node prepares a corresponding entanglement state, and distributes corresponding entanglement particles to Alice and Bob of two communication parties and any one member of three control groups C1, C2 and C3 through a quantum channel; and other members of the three control groups C1, C2 and C3 execute C-by taking the particles sent by the central service node as control quantum bits and | 0) as target quantum bits. The NOT operation generates control particles. The threshold-adjustable optimal controlled quantum stealth transmission method for any unknown n particles has the advantages that the threshold-adjustable optimal controlled quantum stealth transmission method for any unknown n particles realizes the safety and flexibility of information transmission.

The invention discloses a measurement equipment-independent quantum direct communication method, which comprises the following steps of: randomly preparing an entangled quantum bit in a two-photon state through Alice, and randomly preparing a quantum bit in a single-photon state in one of four quantum states of {|0>, 1>, |+> and |->} through Bob; the Alice sends the quantum bit of one photon in the entangled state to the Charlie and keeps the quantum bit of the remaining entangled state of one photon, and the Bob sends the randomly prepared quantum bit of the single photon state to the Charlie; after the Charlie receives the quantum bits sent by the Alice and the Bob, Bell state measurement is executed, then a measurement result is published through a classical channel, and the Alice executes unitary operation to complete quantum teleportation. According to the coding mode, quantum storage can be removed.

The invention provides an integrated optical chip system for distributed security quantum information processing. The integrated optical chip system comprises a server integrated optical quantum chip and a user integrated optical quantum chip. The server integrated optical quantum chip comprises a configurable entanglement multi-photon source which is used for generating a plurality of photons and outputting the photons to a server linear optical network and a user linear optical network according to wavelengths; the server linear optical network which is used for preparing an initial state for the photons output by a wavelength division multiplexer, carrying out unitary transformation and linear combination, carrying out combination and carrying out projection measurement on the combined photons; and a user integrated optical quantum chip which transmits linear term coefficients through quantum teleportation so as to linearly combine each term of unitary transformation in the server integrated optical quantum chip. The server cannot know the specific computing task of the user, and the user is informed of the result through a classic channel after computing is completed. By using the technical scheme of the invention, the computing privacy of the user can be protected.

The invention belongs to the technical field of computer software and discloses a method and a system for increasing the number of quantum entanglement interfaces. The system comprises a quantum measurement module, an entanglement state preparation module, a channel acceleration module of a basic link, a channel acceleration module of a long link and an incremental preparation module. The quantumis described as the complex inner product vector space of the system state space by the quantum measurement module. The entanglement generation module realizes many quantum communication tasks, such as dense quantum coding, quantum teleportation and so on, realizes quantum computation and prepares the initial entanglement effectively. The whole process of quantum computation deals with the information encoded in quantum states. The invention establishes a quantum channel between two non-adjacent interfaces through a relay interface through a channel acceleration module of a long link.

The invention discloses a high-dimensional asymmetric bidirectional controlled quantum teleportation method. The method comprises the following steps: step 1, establishing a quantum communication joint system based on three parties of Alice, Bob and Charlie; step 2, Alice and Bob respectively carry out generalized Bell measurement and generalized single particle measurement on particles owned by Alice and Bob, and publish measurement results; 3, the supervisor Charlie carries out single particle measurement on particles owned by the supervisor Charlie and publishes a measurement result; and step 4, the Alice and the Bob construct a full view of the original quantum state sent by the opposite side by using the measurement result. Bidirectional transmission of quantum information can be realized; the success probability of transmission and restoration of quantum information is 1, the difficulty of specific communication control is greatly reduced, and bidirectional controlled invisible state transmission is easier to physically realize.