Measuring the State of a Bosonic Two-Mode Quantum Field
R. Walser · Physical Review Letters · 1997
A measurement scheme is proposed to determine the state of a bosonic two-mode system completely. Without relying on the existence of a reference field, we reconstruct the quantum state from joint number measurement only, in case $[\mathit{\ensuremath{\rho}},{\stackrel{^}{N}}_{\mathrm{tot}}]\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$. Based on an analogy to angular momentum, we have obtained an explicit inversion procedure for the density matrix of the system and discuss its application.