Quantum interference with molecules: The role of internal states
arXiv:quant-ph/0502156 · doi:10.1103/PhysRevA.71.062103
Abstract
Recent experiments have shown that fullerene and fluorofullerene molecules can produce interference patterns. These molecules have both rotational and vibrational degrees of freedom. This leads one to ask whether these internal motions can play a role in degrading the interference pattern. We study this by means of a simple model. Our molecule consists of two masses a fixed distance apart. It scatters from a potential with two or several peaks, thereby mimicking two or several slit interference. We find that in some parameter regimes the entanglement between the internal states and the translational degrees of freedom produced by the potential can decrease the visibility of the interference pattern. In particular, different internal states correspond to different outgoing wave vectors, so that if several internal states are excited, the total interference pattern will be the sum of a number of patterns, each with a different periodicity. The overall pattern is consequently smeared out. In the case of two different peaks, the scattering from the different peaks will excite different internal states so that the path the molecule takes become entangled with its internal state. This will also lead to degradation of the interference pattern. How these mechanisms might lead to the emergence of classical behavior is discussed.
arXiv comment12 pages, 4 eps figures, quality of figures reduced because of size restrictions
References in corpus (7)
- Decoherence of matter waves by thermal emission of radiation
- The wave nature of biomolecules and fluorofullerenes
- Collisional decoherence reexamined
- Theory of decoherence in a matter wave Talbot-Lau interferometer
- A search for a border between classical and quantum worlds
- Influence of molecular temperature on the coherence of fullerenes in a near-field interferometer
- Towards the elusive Efimov state of the ^4He_3 molecule through a new atom-optical state-selection technique