We consider the nondistortion quantum interrogation (NQI) of an atom prepared in a quantum superposition. By manipulating the polarization of the probe photon and making connections to interaction free measurements of opaque objects, we show that nondistortion interrogation of an atom in a quantum superposition can be done with efficiency approaching unity. However, if any component of the atom's superposition is completely transparent to the probe wave function, a nondistortion interrogation of the atom is impossible.
@article{arxiv.quant-ph/0105023,
title = {High efficiency Nondistortion Quantum Interrogation of atoms in quantum superpositions},
author = {Xingxiang Zhou and Zheng-Wei Zhou and Guang-Can Guo and Marc J. Feldman},
journal= {arXiv preprint arXiv:quant-ph/0105023},
year = {2007}
}