Two-mode squeezed states as Schrodinger cat-like states

In recent years, there has been an increased interest in the generation of superpositions of coherent states with opposite phases, the so-called photonic Schrodinger cat states. These experiments are challenging, and, so far, cats involving only small photon numbers have been implemented. Here, we propose to consider two-mode squeezed states as examples of Schrodinger cat-like states. For this, we apply criteria that aim to identify macroscopic superpositions in a more general sense. We extend some of these criteria to the two-mode continuous variable regime. Furthermore, we compare the size of states obtained in several experiments and discuss experimental challenges for further improvements. Our results not only promote two-mode squeezed states for exploring quantum effects at the macroscopic level but also provide direct measures to evaluate their usefulness for quantum metrology. (C) 2015 Optical Society of America