Comparing entanglement and identity effects in tunnelling

Abstract

The probability of simultaneous tunnelling of two particles is modified when the system is in a non-separable state, either entangled or symmetrised. We compare both effects in the rectangular potential barrier by evaluating the transmission rates in superposition states. For large momenta, their simultaneous presence greatly changes the form of the transmission rates. The joint effects are much larger than the superposition ones. Moreover, there are significant differences between bosons and fermions. We present an unified view of the combined effects as a quantum interference phenomenon. The analysis also illustrates a novel aspect of exclusion in entangled systems, the existence of superposition states one of whose terms is forbidden by Pauli's principle.