Quantum Random Number Generation via Birefringent Optical Cavity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional random number generators (RNGs) are limited by pseudo-randomness, slow speed, and sensitivity to temperature and external conditions, requiring correction for significant fluctuations and zero bits, which hinders their efficiency in producing truly random numbers.

Innovation Solution

The use of a highly coherent beam source interacting with a birefringent medium within an optical cavity, where the beam's polarization is rotated and subdivided, generating randomized light output that is read by a pixelated photodetector, producing inherently random and parallel bit streams.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional optical noise sources are used to generate random numbers, then random number generation is possible, but the system exhibits slow speed and requires correction circuitry due to significant fluctuations and zero bits

Engineering Contradiction:
Improverandom number generation speedVSAvoidrandom number quality
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The invention changes the fundamental parameter being measured from optical noise intensity to photon arrival timing. By detecting when photons arrive at the photodetector rather than measuring noise fluctuations, the system achieves both high speed (no waiting for noise thresholds) and high reliability (true randomness without zero bits), resolving the contradiction between productivity and reliability

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention replaces the mechanical/electronic noise measurement system with a quantum-optical photon detection system. Instead of measuring electrical noise fluctuations that require correction, the system detects individual photon arrival events, which inherently provide true randomness without requiring Von Neumann correctors or filtering, thus improving both speed and reliability

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If optical noise sources are used in conventional RNGs, then random number generation is possible, but the system requires correction circuitry and filtering due to temperature sensitivity and external condition fluctuations

Engineering Contradiction:
Improverandom number qualityVSAvoidcorrection circuitry requirements
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention replaces temperature-sensitive optical noise measurement with quantum-optical photon arrival detection. Photon arrival times are fundamentally random and insensitive to temperature and external conditions, eliminating the need for Von Neumann correctors and filtering circuitry, thus improving reliability while reducing device complexity

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The photon arrival detection system is self-correcting by its nature. Each photon arrival event is an independent quantum event that inherently provides true randomness without requiring external correction mechanisms. The system serves itself by using the quantum nature of light directly, without needing additional correction circuitry

Inventive Principle:
Principle #25Self-service

3Productivity

If conventional optical noise methods are used, then random number generation is possible, but the system is slow as it must wait for noise levels to rise above thresholds

Engineering Contradiction:
Improverandom number generation speedVSAvoidwaiting time for noise thresholds
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The invention replaces the time-consuming noise threshold detection with immediate photon arrival detection. Photons arrive continuously and can be detected instantaneously, eliminating the waiting time required for noise levels to rise above thresholds, thus dramatically improving productivity without time loss

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach generates true randomness independent of pseudo-random algorithms, enables rapid bit production, and provides a scalable solution for parallel computing applications, overcoming the limitations of conventional RNGs.

Implementation Method 1

a birefringent medium positioned within the optical cavity to receive the beam and produce a new subdivided beam at least each roundtrip traversal

Methodology Applied
Scientific EffectBirefringence: Birefringence

Implementation Method 2

Devices may be used to rotate the state of polarization of the light, maintaining a 'mixed quantum state' (relative to the axes of a birefringent medium)

Methodology Applied
Scientific EffectPolarization rotation: Polarisation

Implementation Method 3

a photodetector positioned to receive the randomized energy from the cavity and convert the randomization energy into a parallel randomized output signal

Methodology Applied
Scientific EffectPhotoelectric effect: Photoelectric Effect

Implementation Method 4

The cavity reflects the light back-and-forth through a birefringent material within the cavity, along with polarization rotating elements

Methodology Applied
Scientific EffectOptical reflection: Reflection

Data Source

PatentEP3736687B1Generation of random numbers through the use of quantum-optical effects
Publication Date: 2022.04.06 SCARLETT CAROL Y
  • EP3736687B1 patent drawingFigure 1
  • EP3736687B1 patent drawingFigure 2
  • EP3736687B1 patent drawingFigure 3

AI summary

An optical system uses a birefringent medium disposed within an optical cavity, receives an input beam that may be non-coherent or coherent, and produces a randomization energy from the input beam, by creating birefringent induced beam subdivisions each cavity traversal, where after a threshold number of beam traversals have occurred, a randomized energy distribution is created. That randomized energy distribution is read by a photodetector and converted into a random number by a randomization processing device.