Photon Detectors: Absorption or Further Testing?

[StevieTNZ]

Do photon detectors necessarily need to absorb the photon to detect it (i.e. can photon detectors exist that make the detection but allow us to perform further tests on the photon)?

 

[davenn]

"photon Detectors" aka Photomultiplier tubes work on the principal of the photon(s) striking an electrode which emits electrons which strike other electrodes emitting more electrons in a cascading effect, producing a measurable current flow, the "photoelectric effect" first discovered by Heinrich Hertz in the late 1800's and was followed up by work done by Elster and Geite.

I personally am unaware of any photon detectors that work the way you describe, maybe some one else will chime in with that possibility :)

cheers
Dave

 

[Vanadium 50]

A detector is changed by the photon, and the photon (if it still exists) is changed by the detector. This is a statement that does not depend on the details of the detection mechanism.

You can only step in the same stream once.

 

[Dale]

You might be interested in so-called "weak measurement". I don't know much about it, but you clearly have an internet connection

 

[Wolfgang2b]

Might be possible via Quantum Non demolition measurement

Chk this article out
"Quantum non-demolition measurement allows physicists to count photons without destroying them"
http://www.physorg.com/news197873165.html