Reduction of the field spectral linewidth in a quantum-box semiconductor laser and its experimental demonstration using a quantum well laser in a high magnetic field

We investigate properties of the field spectrum of semiconductor lasers with quantum well box effects. The analysis reveals a significant reduction of the spectrum linewidth due to the quantum well box effect. This prediction is successfully demonstrated experimentally by placing a quantum well laser in a high magnetic field, in which Lorentz force as well as the quantum well potential forms a quasi-zero-dimensional electronic system. Furthermore, changes in the spontaneous emission spectrum of TE mode and TM mode are observed with the increase of the magnetic field, which results from suppression of anisotropic properties of the quantum well structure.