Poster: Interatomic Coulombic decay in double quantum dots

FEDERICO M. PONT; ANNIKA BANDE; LORENZ S. CEDERBAUM

Mainz

Encuentro; ICD Research Unit Kick-Off Meeting; 2013

We demonstrate that Interatomic Coulombic Electron Capture (ICEC)is possible in double quantum dots. It was first proposed for atomicdimers and is a process were one electron is captured by one of theatoms and the released energy is used to ionize the neighboring atom.ICEC is related to the Inter Coulombic Decay (ICD) processes, and itcan be conceptualized using a virtual photon mechanism as well, butit is not a resonant process. The model used consists of two aligneddots separated by a distance R in a quasi-onedimensional nanowire.We are interested in a regime where the dots are not identical, theyhave only one bound state each, and the separation R is long enoughto prevent electrons from tunneling between them. Since ICEC is nota resonant process, it can be in principle accessible in a wide rangeof energies. However we have found that in the quasi-onedimensionalregime, the process shows enhancements for some definite values ofthe incoming electron momentum. In this case the reaction probabil-ity for ICEC was estimated to be of the order of 1%. Another ICECrelated process was analyzed by allowing one of the dots to have onemore bound state. In this setup a delocalized resonance between dots,which can decay through ICD, aids the process and a huge increase inthe reaction probability is found reaching values up to 35%.