  Quantum reading aims at retrieving classical information stored in an optical
memory with low energy and high accuracy by exploiting the inherently quantum
properties of light. We provide an optimal Gaussian strategy for quantum
reading with phase-shift keying encoding that makes use of squeezed coherent
light and homodyne detectors to largely outperform the Standard Quantum Limit,
even in the presence of loss. This strategy, being feasible with current
quantum optical technology, represents a viable prototype for a highly
efficient and reliable quantum-enhanced optical reader.
