The ultraviolet laser from individual ZnO microwire with quadrate cross section.

The ZnO microwires with quadrate cross section were synthesized by chemical vapor deposition method. The ultraviolet laser with the Fabry-pérot cavity modes was realized from an individual ZnO microwire. Under the low excitation power densities, the amplified spontaneous emission was observed from the ZnO microwire, while the lasing action was observed under the high excitation power densities. The ZnO microwire exhibited low threshold excitation intensity of 58 kW/cm(2) and quality factor of 485. The characteristics and possible lasing mechanism were investigated in detail.