Quantum cipher based on phase inversion

Patent metadata

Field	Value
Publication number	US-11310040-B2
Application number	US-202016806430-A
Country	US
Kind code	B2
Filing date	Mar 2, 2020
Priority date	Mar 1, 2019
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

Methods, systems and computer readable media are disclosed for providing a quantum cipher based on phase inversion, A shared key is established between a first party and a second party. A Hadamard transformation is applied to a message intended for a second party from the first party to produce an equal superposition state. A key phase inversion is applied to the output of the Hadamard transformation. A multiple phase inversion transformation is applied to the output of the key phase inversion to produce an encrypted quantum state with a uniform probability and relative phase distributions. The result is sent to the second party.

First claim

What is claimed is:

1. A method of providing a quantum cipher based on phase inversion, the method comprising:
establishing a shared key between a first party and a second party;
applying a Hadamard transformation to a message intended for a second party from the first party to produce an equal superposition state;
applying a key phase inversion to the output of the Hadamard transformation;
applying a multiple phase inversion transformation to the output of the key phase inversion to produce an encrypted quantum state with a uniform probability and relative phase distributions; and
sending the result to the second party.

2. The method of claim 1 wherein the applying a Hadamard transformation to a message intended for a second party from the first party to produce an equal superposition state, the applying a key phase inversion to the output of the Hadamard transformation, and the applying a multiple phase inversion to the output of the key phase inversion to produce an encrypted quantum state with a uniform probability and relative phase distributions are performed by a quantum computer.

3. The method of claim 1 wherein the quantum cipher is used for communications between a UE and a core.

4. The method of claim 1 wherein the Hadamard transformation is performed in accordance with the formula



ψ
m

〉

=

H

⊗
n

⁡

(


m
〉

)

=

1

N

⁢

∑

x
=
0

N
-
1

⁢

(

-
1

)

m
·
x

⁢


x
〉

.

5. The method of claim 1 wherein the key phase inversion is performed in accordance with the formula
Λ k =I− 2| k><k|.

6. The method of claim 1 wherein the multiple phase inversion transformation is performed in accordance with the formula
|ψ c =γ k,d |ψ′ c .

7. The method of claim 1 further comprising retrieving the message from the result, the retrieving comprising:
applying a multiple phase inversion transformation to the received message;
applying a key phase inversion to the output of the multiple phase inversion transformation; and
applying a Hadamard transformation to the result from the key phase inversion.

8. A system comprising:
a UE including a first quantum computing element; and
a core network including a second quantum computing element;
wherein the first quantum computing element provides a quantum cipher based on phase inversion for a message sent from the UE to the core network;
wherein the second quantum computing element provides a quantum cipher based on phase inversion for a message sent from the core network to the UE, wherein the quantum cipher based on phase inversion is provided by the method comprising: establishing a shared key between a first party and a second party: applying a Hadamard transformation to a message intended for a second party from the first party to produce an equal superposition state; applying a key phase inversion to the output of the Hadamard transformation; applying a multiple phase inversion transformation to the output of the key phase inversion to produce an encrypted quantum state with a uniform probability and relative phase distributions; and sending the result to the second party.

9. The system of claim 8 wherein the applying a Hadamard transformation to a message intended for a second party from the first party to produce an equal superposition state, the applying a key phase inversion to the output of the Hadamard transformation, and the applying a multiple phase inversion to the output of the key phase inversion to produce an encrypted quantum state with a uniform probability and relative phase distributions are performed by a quantum computer.

10. The system of claim 8 wherein the Hadamard transformation is performed in accordance with the formula



ψ
m

〉

=

H

⊗
n

⁡

(


m
〉

)

=

1

N

⁢

∑

x
=
0

N
-
1

⁢

(

-
1

)

m
·
x

⁢


x
〉

.

11. The system of claim 8 wherein the key phase inversion is performed in accordanc

Assignees

• Parallel Wireless Inc

Inventors

• MENON Vikram
• Chattopadhyay Ayan

Classifications

• H04L9/06

  the encryption apparatus using shift registers or memories for block-wise {or stream} coding, e.g. DES systems {or RC4; Hash functions; Pseudorandom sequence generators} · CPC title

• H04L9/0858 Primary

  Details about key distillation or coding, e.g. reconciliation, error correction, privacy amplification, polarisation coding or phase coding · CPC title

• H04L9/0852 Primary

  Quantum cryptography (transmission systems employing electromagnetic waves other than radio waves, e.g. light, infrared H04B10/00; wavelength-division multiplex systems H04J14/02; WDM arrangements H04J14/03) · CPC title

• G06F17/145

  Square transforms, e.g. Hadamard, Walsh, Haar, Hough, Slant transforms · CPC title

• G06N10/00

  Quantum computing, i.e. information processing based on quantum-mechanical phenomena · CPC title