Granted Patent B2

US 12,647,260 · App. 19/337,685 · Granted Jun 2, 2026

Inventor: Mingjun Wang (Saratoga, CA)

Assignee: Homatch.ai

H04L9/0858

Abstract

Claims (33)

1 . A method for secure quantum communication, comprising:

generating a photon;

modulating at least two quantum state dimensions selected from the group consisting of orbital angular momentum (OAM), polarization, and phase of the photon to form a composite quantum state;

directing the photon to an emission point on a structure having a defined spatial coordinate corresponding to classical data; and

emitting the photon from the emission point into a quantum channel;

wherein the composite quantum state and spatial coordinate together encode secure information.

2 . The method of claim 1 , wherein the structure comprises a double-helix geometry defined by a helix radius and pitch, and includes multiple discrete emission points distributed along its surface.

3 . The method of claim 1 , wherein the spatial coordinate encodes a classical bit, and wherein the emission point is dynamically selected based on information content.

4 . The method of claim 1 , further comprising:

detecting the emitted photon at a receiver;

decoding the classical data from the spatial coordinate of the emission point;

decoding the composite quantum state from at least one of the OAM, polarization, or phase measurement.

5 . The method of claim 4 , further comprising applying a classical error correction code to the classical data and a quantum error correction code to quantum data encoded in the composite quantum state.

6 . The method of claim 5 , wherein the quantum error correction code comprises a Shor code, a Steane code, or a surface code.

7 . The method of claim 5 , wherein the classical error correction code comprises a Reed-Solomon code.

8 . The method of claim 1 , wherein emission points are randomized among positions on the structure to introduce spatial entropy for key distribution protocols.

9 . The method of claim 1 , further comprising generating a secure quantum key from two or more photons emitted from emission points of the structure for secure communication between a receiver and a sender that includes the structure.

10 . The method of claim 9 , wherein the secure quantum key is generated according to a quantum key distribution protocol that includes the BB84 quantum key distribution protocol or the E91 quantum key distribution protocol.

11 . The method of claim 9 , wherein the secure quantum key is generated using a measurement device independent quantum key distribution (MDI-QKD) protocol in a system that comprises a sender, a receiver, and an untrusted relay node configured to perform Bell-state measurements on photons received from the sender and the receiver, and wherein the sender and receiver generate shared keys based on the measurement outcomes.

12 . The method of claim 9 , wherein the secure quantum key is generated according to a quantum key distribution protocol that includes a continuous-variable quantum key distribution (CV-QKD) protocol and the CV-QKD protocol includes encoding information in quadrature components of an electromagnetic field of the photon.

13 . A quantum communication system, comprising:

a photon source configured to emit single photons;

at least one modulator configured to adjust two or more quantum state dimensions selected from orbital angular momentum (OAM), polarization, and phase;

a structure having a plurality of emission points with unique spatial coordinates;

a control module for selecting emission points based on classical data mapping; and

a receiver configured to extract classical and quantum information from received photons.

14 . The system of claim 13 , wherein the structure is fabricated from a photonic-compatible material selected from the group consisting of silicon nitride, lithium niobate, fused silica, and glass.

15 . The system of claim 13 , wherein the control module dynamically adjusts emission point selection according to a pseudorandom sequence synchronized between sender and receiver.

16 . The system of claim 13 , wherein quantum key distribution is performed using an extended BB84 protocol combining polarization basis selection and spatial encoding.

17 . The system of claim 13 , wherein the receiver includes a spatial decoding module, an OAM mode sorter, a polarization analyzer, and an interferometric phase detector.

18 . The system of claim 13 , wherein the structure includes multiple parallel helix chains operating as separate quantum channels under a shared control module.

19 . The system of claim 13 , wherein each spatial coordinate encodes a classical bit, and wherein the control module is configured to dynamically select an emission point for each photon based on information content.

20 . The system of claim 13 , wherein the plurality of emission points are arranged linearly, in a planar grid, radially, along a spiral path, or along a circular path.

Assignments (1)

Continuity (3)

References Cited (16)