Harmonic oscillator driven by a quantum current
John J. Slosser, Pierre Meystre, Samuel L. Braunstein · Physical Review Letters · 1989
We show that under certain circumstances a simple quantum harmonic oscillator driven by a quantum current evolves to unique pure states even if started as a mixed state. In various limits, these states exhibit nonclassical properties such as sub-Poissonian statistics, or more interestingly resemble macroscopic superpositions.