This experimental verification of a method for taking a “picture” of something without needing reflection of particles to “see it” was announced this month:
“Quantum imaging involves sending one of a pair of entangled photons towards an object while holding on to the other.
For a long while nobody was quite sure what benefit you might get from this entanglement. Some physicists speculated that it could be possible to produce reflection-free images by measuring the entangled twin that you hang on to, even if the other photon never returns.
What Lloyd calculated was that illuminating an object with entangled photons can increase the signal to noise ratio of the reflected signal by a factor of 2^e, where e is the number of bits of entanglement. That’s an exponential improvement.
Now he and a few pals have gone and done the experiment and shown that Lloyd was right on the money. They sent photons towards an object and used the reflection to determine whether the object was present or absent.
When they used entangled photons, this process was much more efficient.
The result is effectively the first quantum image taken with entangled photons.”
Read the full article here.