We present quantum Maxwell-Bloch equations (QMBE) for spatially inhomogeneo
us semiconductor laser devices. The QMBE are derived from fully quantum mec
hanical operator dynamics describing the interaction of the light field wit
h the quantum states of the electrons and the holes near the band gap. By t
aking into account field-field correlations and field-dipole correlations,
the QMBE include quantum noise effects, which cause spontaneous emission an
d amplified spontaneous emission. Tn particular, the source of spontaneous
emission is obtained by factorizing the dipole-dipole correlations into a p
roduct of electron and hole densities. The QMBE are formulated for general
devices, for edge emitting lasers and for vertical cavity surface emitting
lasers, providing a starting point for the detailed analysis of spatial coh
erence in the near-field and far-field patterns of such laser diodes. Analy
tical expressions are given for the spectra of gain and spontaneous emissio
n described by the QMBE. These results are applied to the case of a broad a
rea laser, for which the frequency and carrier density dependent spontaneou
s emission factor beta and the evolution of the far-held pattern near thres
hold are derived. [S1050-2947(99)02803-6].