I Are Expectation Values Measured for Coupled Photons from SPDC?

  • I
  • Thread starter Thread starter emuc
  • Start date Start date
  • Tags Tags
    Coupled Photons
emuc
Messages
31
Reaction score
2
Entangled photons are generated, for example, by parametric down conversion (SPDC). The ordinary photon beam has polarization 0° and the extraordinary photon beam comes with the polarization 90°. Each photon leaves the source in a cone of light. Both cone shells intersect in two beams, which are thus each a mixture of horizontally and vertically polarized photons in equal share.

My question is how are photons related, which do not emerge on the line of intersection of the cone shells but are each clearly assigned to one of the two cone shells.

Does anybody know if this is measured already?
 
Physics news on Phys.org
emuc said:
My question is how are photons related, which do not emerge on the line of intersection of the cone shells but are each clearly assigned to one of the two cone shells.
If the photons are distinguishable - as they would be in this case - they will not be entangled. One will be V, the other H. This is for what is called Type II SPDC. Not being entangled, they act independently as to polarization.
 
Do you know about measurements of expectation values for this case?
 

Thread 'importance of Hanbury Brown and Twiss experiment'

I read Hanbury Brown and Twiss's experiment is using one beam but split into two to test their correlation. It said the traditional correlation test were using two beams........ This confused me, sorry. All the correlation tests I learnt such as Stern-Gerlash are using one beam? (Sorry if I am wrong) I was also told traditional interferometers are concerning about amplitude but Hanbury Brown and Twiss were concerning about intensity? Isn't the square of amplitude is the intensity? Please...
View full post »

Thread 'Prof Mike Wiest's proposed link between quantum and consciousness'

I am not sure if this belongs in the biology section, but it appears more of a quantum physics question. Mike Wiest, Associate Professor of Neuroscience at Wellesley College in the US. In 2024 he published the results of an experiment on anaesthesia which purported to point to a role of quantum processes in consciousness; here is a popular exposition: https://neurosciencenews.com/quantum-process-consciousness-27624/ As my expertise in neuroscience doesn't reach up to an ant's ear...
View full post »

Thread 'Quantum Entanglement is a Kinematic Fact, not a Dynamical Effect'

Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
View full post »

Similar threads

I Problem with the polarization of entangled photons
Replies
7
Views
2K
I Tips on generating entangled photon pair with SPDC entanglement source
Replies
1
Views
2K
I How to distinguish between diagonal vs horizontal/vertical polarization?
Replies
15
Views
3K
I Determination of entanglement by observing only one photon
Replies
20
Views
3K
I Spontaneous parametric down-conversion entanglement using BBO
Replies
4
Views
2K
A Is delayed choice remote entanglement of photons derived from TDSE?
2
Replies
58
Views
4K
I Bell's Inequality => 4 entangled Photons impossible?
Replies
1
Views
2K
I Two Photon Sagnac Source
Replies
5
Views
2K
B Calculating Photon Polarization States with PBS & Wave Plates
Replies
3
Views
2K
Question about spontaneous parametric down conversion
Replies
7
Views
2K

Hot Threads

Recent Insights

Back
Top