The optical properties of GaAs/AlGaAs T-shaped quantum wire (QWR) lasers have been investigated. In particular, we have studied the dependence of the stimulated emission intensity from the pump laser wavelength. We found that for an excitation power above the threshold for stimulated emission of the QWR, only for an excitation energy (= 782 nm) smaller than the absorption band of the multiple quantum well (MQW) lasing condition was achieved. For larger values of the excitation energy ( = 738 nm), only spontaneous emission of the QWR is observed. Furthermore, we have investigated the temperature stability of the QWR laser. We found a constant behavior of the QWR emission intensity in a temperature range from 4 to 40 K indicating a high stability of one-dimensional excitons up to 40 K, while an intensity decrease was measured for higher temperatures.