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Questions related from Neil Salmon
Does anyone have experience of creating a DLM, DLL or SPAWN in the Interactive Data Language (IDL) from a *.c code? This is used to increase the speed of IDL’s computation for particularly slow...
17 July 2025 2,318 0 View
To render images of a water surface in a simulation i'm looking for computer graphics files of such surfaces, in particular those showing a Kelvin Wake or a Bernoulli Hump. These features are...
14 June 2025 968 11 View
Is it possible to know what the degree of squeezing of entangled photons will be in the quantum mechanical process of spontaneous parametric down-conversion (SPDC)? For example, would it be...
30 October 2024 4,405 0 View
In quantum optics the Hong-Ou-Mandel (HOM) effect is seen as a mechanism for creating NOON States from Bell States. Has this been demonstrated experimentally, how efficient is the process and how...
22 October 2024 7,679 0 View
A number of Python modules exisit for modelling the quantum outputs of quantum optical systems. With only one or two optical components and simple quantum states, system outputs can be calculated...
12 October 2024 3,415 3 View
Isn't quantum teleportation a bit of a con, given that you need to transmit information classical to realise it? You might as well just have transmitted the information classically. Furthermore,...
10 October 2024 5,030 2 View
If each photon of an quantum entangled pair of photons is herodyne of homodyne mixed, shifting it to a different frequency band, does this break the quantum entanglement between the two pairs? In...
28 September 2024 3,849 3 View
Knowledge of properties of illicit drugs in the microwave/low frequency parts of the millimetre wave band (10 GHz to 50 GHz) may at least enable a first line of defence in security screening of...
30 July 2024 1,480 6 View
With so many different website-design software packages to choose from, selecting one which is versatile, pleasant to use, guaranteed future-proof and cost-effective becomes difficult. Packages...
19 April 2024 8,657 0 View
A variety of package managers are available for Python, such management being essential if you're using the wide variety of Python packages available for a diversity of applications ranging from...
10 April 2024 2,701 5 View
Finding the best features (sometimes called metrics or parameters) to input into a neural network by trial and error can be a very lengthy process. Classic feature selection methods in machine...
04 June 2023 6,900 14 View
How is the depth and width of a neural network in machine learning chosen for optimal processing? Given that neural networks are tending to be deeper now (thanks to more efficient coding and...
26 January 2021 10,239 3 View
Are there some (simple) rules or conditions which dictate whether a physical process will lead to a state of quantum entanglement of two or more particles or systems? Given the relevance of the...
14 December 2020 7,839 3 View
Is there a simple proof that the signal and idler photons created by spontaneous parametric down-conversion (SPDC) are entangled, whereas those that are created by optical parametric amplification...
29 November 2020 1,679 4 View
Nonlinear materials had a fascinating effect on the technology development. For example, in the 1950/60’s the nonlinearity of ferrites (associated with spinwaves) was exploited for microwave and...
08 May 2019 5,570 2 View
The synthetic crystals of lithium niobate and beta barium borate (BBO) were designed specifically to have the lowest possible power thresholds for nonlinear effects for use in quantum optics. Was...
14 April 2019 5,155 6 View
For quantum entanglement experiments in the mm-wave band it is necessary to have a source of entangled photons. Generating these from a pump of radiation by spontaneous parametric down conversion...
07 March 2019 7,177 0 View
It is likely that the production rate of entangled photons in a non-linear material is proportional to the power of the pump and the non-linear material susceptibility (chi-2). Would anyone know...
19 June 2018 866 9 View
Is is possible to amplify a single photon? If possible, what is the resultant electric field and phase like compared to that of the incident photon? Consider two possible scenarios for this: 1)...
19 June 2018 483 21 View
Quantum entanglement experiments are normally carried out in the regime (hf>kT - where T is the temperature of the instrument) to minimise thermal noise, which means operating in the optical band,...
09 May 2018 5,620 4 View
In quantum entanglement is the entanglement between a pair of entangled photons broken if one of the pair induces stimulated emission? That is one of the pair generates a third photon. Normally...
27 January 2018 5,035 4 View
If one of the two photons of an entangled pair stimulates the generation of a third photon, by stimulated emission, does this destroy the entanglement of the original entangled pair? If it does...
26 January 2018 7,182 12 View
If its possible to create a Bose-Einstein condensate for which no possible Fermi interactions can prevent further collapse and the mass was large enough, could the system collapse into a black...
03 December 2017 3,120 12 View
For development of a concealed weapons detection technology, an AI machine learning trial is being conducted that will train a network measuring features from a non-imaging millimetre wave sensor....
01 January 1970 9,405 0 View