  The Schr\"odinger cat state plays a crucial role in quantum theory, and has
important fundamental as well as technological implications, ranging from
quantum measurement theory to quantum computers. The power of the potential
implications of the cat state lies in the quantum coherence, as measured by the
degree of entanglement, between its microscopic and macroscopic sectors. We
show that in contrast to other cat states, it is possible to choose the states
of the macroscopic sector in a way that the resulting cat state, which we term
as the W-cat state, has quantum coherence that is resistant to the twin effects
of environmental noise -- local decoherence on all the particles and loss of a
finite fraction of its particles. The states of the macroscopic sector of the
W-cat state are macroscopically distinct in terms of their violation of Bell
inequality.

Quantum Physics