Ring Microresonator Entangled Photon Generation via Angular Dispersion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current models for generating entangled photons in azimuthally symmetric systems lack a fully vectorial quantum description, limiting the accuracy of optical wave propagation and design possibilities for new devices.
Innovation Solution
A non-linear optical device with an optical disk or ring microresonator fabricated from a material that exhibits zero angular group velocity dispersion at a specific pump frequency, emitting a frequency comb of entangled photon pairs with frequencies symmetrically placed about the zero-dispersion frequency, utilizing cylindrical coordinates for improved accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a fully vectorial quantum description is used to improve accuracy of optical wave propagation, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent transforms the complex quantum description problem by changing the mathematical parameters from Cartesian coordinates to cylindrical coordinates, and from linear wavevector to angular wavevector. This parameter transformation simplifies the fully vectorial quantum description while maintaining measurement precision, as cylindrical coordinates naturally match the azimuthally symmetric geometry of the microresonator system.
2Ease of operation
If linear wavevector and group velocity are used to model optical wave propagation, then ease of operation is improved, but measurement precision deteriorates for small resonator radii
Solution Approach 1:
The patent inverts the conventional approach by replacing linear wavevector and group velocity with their angular counterparts. Instead of using linear coordinates (k-vector) that work for large resonators, the invention uses angular coordinates (angular wavevector and angular group velocity) that are appropriate for small resonator radii, thereby improving measurement precision while maintaining ease of operation through the natural symmetry of the system.
3Ease of manufacture
If azimuthally symmetric systems are used for FWM, then ease of manufacture is improved, but adaptability deteriorates for generating entangled photons with wide spectral separation
Solution Approach 1:
The patent resolves this contradiction by introducing controlled asymmetry through the use of angular wavevector and angular group velocity in the quantum description. While the physical microresonator maintains azimuthal symmetry for ease of manufacture, the mathematical description employs angular parameters that break the symmetry limitation, enabling the system to generate entangled photons with wide spectral separation by properly accounting for the angular dependence of the FWM process.
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
Facilitates the generation of entangled photon pairs with wide spectral separation and suppresses pair generation for closely spaced modes, enabling new design approaches and potentially leading to advanced optical devices.
Implementation Method 1
FWM in chip-scale microresonators has been proposed as potentially advantageous means for producing narrowband entangled photons
Implementation Method 2
if the resonant disk or ring is composed of a material with a third-order nonlinear susceptibility χ(3) (ρ, z), then upon pumping the resonator with a strong pump beam of frequency ωp
Implementation Method 3
The device comprises an optical disk or ring microresonator fabricated from a material that exhibits an optical nonlinearity able to produce degenerate four-wave mixing (FWM) in response to a pump beam having a pump frequency in a specified effective range. The microresonator is conformed to exhibit an angular group velocity minimum at a pump frequency within the specified effective range such that there is zero angular group velocity dispersion at the pump frequency.
Data Source
AI summary
A non-linear optical device is provided. The device comprises an optical disk or ring microresonator fabricated from a material that exhibits an optical nonlinearity able to produce degenerate four-wave mixing (FWM) in response to a pump beam having a pump frequency in a specified effective range. The microresonator is conformed to exhibit an angular group velocity minimum at a pump frequency within the specified effective range such that there is zero angular group velocity dispersion at the pump frequency. We refer to such a pump frequency as the “zero dispersion frequency”. In embodiments, excitation of the resonator by a pump beam of sufficient intensity at the zero-dispersion frequency causes the resonator to emit a frequency comb of entangled photon pairs wherein the respective frequencies in each pair are symmetrically placed about the zero-dispersion frequency.