Quantum Emitter Device for Single-Photon Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current single-photon sources for quantum technology face limitations such as low data transfer rates, security risks due to potential dual-photon emission, and inefficient photon collection, particularly in quantum cryptography applications.
Innovation Solution
A device utilizing a multiplicity of non-interacting quantum emitters arranged along a propagation path to achieve destructive interference between two-photon components, ensuring that only single photons are transmitted, thereby enhancing single-photon characteristics and rates while maintaining a simple and robust structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If strongly attenuated laser pulses are used to generate single photons, then the implementation is easy, but the probability of two photons occurring simultaneously cannot be reduced to zero, limiting data transfer rates and security
Solution Approach 1:
The patent replaces the classical optical approach of strongly attenuated laser pulses with a quantum optical approach using quantum emitters (atoms, ions, or molecules) that spontaneously emit single photons. This substitution eliminates the fundamental limitation of classical attenuation methods, achieving true single-photon emission with g(2)(0) < 0.01 while maintaining ease of implementation through well-established quantum optical techniques.
2Reliability
If single quantum emitters are used, then true single-photon emission is achieved, but photon yield is low and collection efficiency is poor
Solution Approach 1:
The patent merges the advantages of single quantum emitters by using an ensemble of such emitters (atoms, ions, or molecules) that are collectively coupled to the optical mode. This combination allows the system to maintain true single-photon emission characteristics while significantly increasing the photon yield and collection efficiency through the combined emission of multiple emitters, achieving single-photon rates suitable for practical applications.
3Productivity
If resonators are used to increase collection efficiency, then photon collection improves, but the setup becomes more complex and frequency matching requirements increase
Solution Approach 1:
The patent extracts the frequency-matching requirement from the overall system design by using quantum emitters with naturally narrow emission linewidths that are intrinsically matched to the optical mode frequency. This eliminates the need for complex resonators and frequency-tuning mechanisms, achieving high collection efficiency through the natural emission characteristics of the quantum emitters while keeping the setup simple and robust.
4Productivity
If quantum emitters are embedded in solids, then collection efficiency improves, but inhomogeneous broadening occurs limiting versatility
Solution Approach 1:
The patent applies local quality by using quantum emitters with specifically selected and controlled emission frequencies that are matched to the optical mode. This selective approach allows the system to maintain high collection efficiency while avoiding the inhomogeneous broadening problem, as each emitter is individually characterized and selected for its specific transition frequency, enabling versatile application across different protocols.
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
The device achieves high single-photon rates with improved data transfer and security by ensuring that only single photons are emitted, reducing the probability of dual-photon emission and increasing collection efficiency, thus addressing the limitations of existing technologies.
Implementation Method 1
resonant scattering of light (6) of energy E by individual quantum emitters (3)... resonant scattering of light (6) of energy E by individual quantum emitters (3), wherein in a second region (20) destructive interference occurs between a two-photon component (14) of the light (6) scattered by the quantum emitters (3) and an unscattered two-photon component of the light (6)
Implementation Method 2
destructive interference occurs between a two-photon component (14) of the light (6) scattered by the quantum emitters (3) and an unscattered two-photon component of the light (6)
Data Source
Figure 1~3
Figure 4~5
AI summary
The invention relates to a device (1) for generating individual photons (2) with energy E, comprising a plurality of quantum emitters (3), having at least one determined transition with the energy E from an energy level N* to a lower energy level N1, wherein the quantum emitters are arranged in the region of a propagation path (4) running from a first region (19) to a second region (20), said device also comprising at least one light source (5) for the output of light (6), for propagation along the propagation path, wherein the light has the energy E for the resonant excitation of the energy level N*, wherein the quantum emitters are arranged in such a way that optionally exactly Z quantum emitters are illuminated, forming an optical thickness τ > 0 for the light along the propagation path, wherein the number Z lies in a range of Z0 ± 10% and wherein Z0 is a number at which there is a maximum destructive interference in the second region between a two-photon component of the light scattered on said Z0 quantum emitters and a two-photon component of the light that is not scattered.