Minimum uncertainty states and squeezed states from a sum uncertainty relation

Abstract

Heisenberg's uncertainty relation is at the origin of understanding minimum uncertainty states and squeezed states of light. In the recent past, the sum uncertainty relation was formulated by Maccone and Pati [L. Maccone and A. K. Pati, Phys. Rev. Lett. 113, 260401 (2014)] and is claimed to be stronger than the existing Heisenberg-Robertson product uncertainty relation. We analyze the minimum uncertainty states for the sum uncertainty relation using the variational approach. We claim that the minimum uncertainty states for the sum uncertainty relation are always the minimum uncertainty states for the traditional product uncertainty relation, using the example of position-momentum pair as well as angular momentum operators. We show that the coherent and squeezed states of radiation remain completely unaffected by the sum uncertainty relation.