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  single photon double slit experiment, resetting the detector material after each impact

+ 1 like - 2 dislike

What is the experimental outcome of a single photon/electron double slit experiment under the constraint that after each detection the detector material is reset to the original state ie, in the limit it is substituted by another detector sheet, or photographic plate.

Of course that the impact positions should be recorded in a computer to construct the accumulated final image.

Closed as per community consensus as the post is high-school or undergraduate level
asked May 26, 2015 in Closed Questions by HelderVelez (-10 points) [ no revision ]
recategorized May 27, 2015 by dimension10
Most voted comments show all comments

Why should the resetting of the detector between measuring two data points have an impact on the accumulated final outcome? From basic quantum mechanics it is not expected to have one, so the purpose of this question is not quite clear to me.

@HelderVelez I really dont understand what you are up to here. The double-slit experiment is well understood theoretically and its outcome is known for decades, so questening and testing  such well established physics again and again and again offers no new insights. Also, at some places a simplified version of the double-slit experiment is teached alteady at high-school. So I have some difficulties in understanding what graduate-level+ physics your question contains.

I am therefore voting to close as not graduate-level+ physics

@Dilaton, To avoid uninteresting comments (high-school etc) and distracting answers I can say that I'm an old times electronic engineer and I can interpret the experiments, their outcomes and the underlying theory.  I value experiments, arguments, etc.    

Flag WHY ?

Before the Q is closed I want to say tanks 'obrigado/ευχαριστώ' to Anna. Because she is an experimentalist I know that she have done her best, without prejudice.  

Most recent comments show all comments

In the spirit of this question, between detections the 'reset/randomization/thermalization' of the walls, slits, masks, etc, in the path of the photons should be addressed. Not now.  

@Dilaton In any subject that I study I pay attention to : what is presumed (details not written or not tested) ?   (I'm starting with QM, now). From your comment and Anna's answer I'm tempted to accept that the experiment was not performed.  If this is the case I'will mention the why of my question, in the end.  

1 Answer

+ 3 like - 0 dislike

This is a strange experimental request, mainly because of the dimensions involved. Here is a screen with single photons impinging . In the first second single points appear, of a size of the order of a few square nanometers. Each falls on  a random (x,y) spot on the material of the screen . The distances of one spot at time t to the other at time t1 is random and very far away, counting molecular distances.

This is more apparent when the detecting element is a TV camera, as in this video at around the 3'52". The    camera  works by  the photon hitting a molecule on the screen, generating a photoelectron which is amplified   by the camera. No gratings or scanning slits for position. By construction the same electron will not be there for the next photon,  so it is effectively a reset.

You do not state what you expect, but it is evident from the many experiments available on videos that the interference pattern appears even with a reset of the detecting element.

answered May 27, 2015 by anna v (2,005 points) [ revision history ]
edited May 28, 2015 by anna v

Look, and compare the 1st screen, at 1, 10, 20, 40 seconds. Do they look similar ? NO, is only imo. When photons arrive at 45 seconds they will find a pristine detector plus, plus, plus lots of energy already deposited in the detector.    

I can not take for granted ' interference pattern appears even with a reset of the detecting element.   

in the second exp (video) the discriminator in the position is a grating that is never reseted, I suspect. 

The detector in the first video for each impinging photon is a tiny( 10X10 nanometer ^2 )bit of the molecules of the screen.  The size is such that the probability of another random photon hitting the same spot (classical probability) is tiny. In a sense each photon has its own individual tiny screen. No need for reset.

I replaced the link where the detector is a TV camera, please read the edit.

I have to say that I am not of the opinion that the photon goes through both slits, as the commenters of the experiment assume. It is just the probability  ( see at 4" 28") that covers both slits. But that  is another story.

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