Quasi-Deterministic Single-Photon Source With Active Frequency Multiplexing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current on-demand single-photon sources are resource-intensive and face challenges in achieving high emission probability with efficient coupling and reduced environmental sensitivity, while existing frequency-multiplexed sources are limited by modulation bandwidth and require multiple laser sources.
Innovation Solution
A quasi-deterministic single-photon source using active frequency-multiplexing with a pulse shaper arrangement and optical frequency conversion, enabling wavelength tunability and reduced resource requirements, with a single-photon spectrometer to detect and reshape optical pulses for deterministic single-photon emission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If active frequency-multiplexing is used to achieve quasi-deterministic single-photon emission, then the emission probability is improved, but the device complexity increases due to the need for pulse shaper arrangement and spectral monitoring
Solution Approach 1:
The patent implements feedback control by using a single-photon spectrometer to detect the spectral content of heralding photons and using this information to control the pulse shaper arrangement. This closed-loop feedback system enables the pulse shaper to dynamically adjust and select the correct frequency component from the broadband pulse, ensuring that the heralded photon and the selected pulse component are frequency-matched, thereby achieving quasi-deterministic single-photon emission with high emission probability.
Solution Approach 2:
The patent introduces a pulse shaper arrangement as an intermediary component between the broadband light source and the frequency conversion process. This intermediary device selectively shapes the spectral content of the broadband pulse based on the detected heralding photon frequency, acting as a mediator that ensures frequency matching without requiring multiple fixed-frequency laser sources, thus managing system complexity while maintaining high emission probability.
2Adaptability or versatility
If multiple frequency bins are used for frequency-multiplexing, then the available bandwidth is improved, but the resource consumption increases due to the need for multiple high-power pulsed laser sources
Solution Approach 1:
The patent employs a single broadband pulsed laser source that can provide photons across a wide frequency spectrum, making it a universal source that replaces multiple frequency-specific laser sources. By combining this universal broadband source with a pulse shaper arrangement that can selectively extract any frequency component within the bandwidth, the system achieves multi-functionality, allowing operation across multiple frequency bins without requiring proportional numbers of laser sources.
Solution Approach 2:
The patent segments the broadband spectral output from a single laser source into multiple frequency bins using a pulse shaper arrangement. Instead of using one laser source for each frequency bin, the system generates a broadband pulse and then segments it into the required frequency components on-demand based on the heralding photon detection, thereby reducing the total number of laser sources while maintaining access to multiple frequency bins.
3Device complexity
If conventional optical phase-modulators are used for frequency-shifting, then the device complexity is reduced, but the modulation bandwidth is limited which reduces the number of usable frequency bins
Solution Approach 1:
The patent replaces conventional optical phase-modulators with a pulse shaper arrangement that uses spectral filtering and time-domain gating mechanisms. This substitution enables the system to achieve frequency selection and switching at rates determined by the pulse duration and spectral resolution rather than being limited by the modulation bandwidth of electronic phase-modulators, thereby significantly increasing the effective modulation bandwidth and the number of usable frequency bins while managing device complexity through optical rather than electro-optical mechanisms.
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 solution achieves high repetition rates and indistinguishable single-photon emission with reduced resource consumption, minimizing environmental sensitivity and optical losses, allowing for efficient production of single photons across a large bandwidth.
Implementation Method 1
These heralded photon sources exploit the fact that pairs of correlated photons are produced spontaneously in certain nonlinear optical interactions under a strong pump, for example in spontaneous parametric down-conversion in which a fission event of pump photons creates two lower-energy photons.
Implementation Method 2
a pulse shaper arrangement operable at least over the available bandwidth for active frequency-multiplexing of heralding photons ΔfMUX and adapted for reshaping a broadband optical pulse
Implementation Method 3
An optical frequency conversion means is provided which is adapted for converting the heralded photon corresponding to the detected heralding photon into a single output photon with deterministic source frequency fsrc upon irradiation with a reshaped optical pulse
Data Source
AI summary
A quasi-deterministic single-photon source and method of generating single photons on demand are disclosed. The single-photon source includes photon pair generation for generating a heralding and heralded photon in a frequency-correlated photon pair, a single-photon spectrometer adapted to detect the heralding photon and to generate an output signal that is indicative of the frequency of the detected heralding photon, a pulse shaper arrangement for reshaping a broadband pulse, and an optical frequency conversion means for converting, upon irradiation with a reshaped pulse, a heralded photon into a single output photon with deterministic source frequency. The pulse shaper arrangement is configured to select, based on the spectrometer output signal, only frequency components of the broadband pulse that substantially coincide with the heralding photon frequency or with a constant detuning thereof.