Opposite Temperature Effects of Quantum-Dot Laser under Dual-Wavelength Operation

The authors discover opposite temperature effects when the quantum-dot (QD) laser is controlled to simultaneously oscillate at two modes in the external cavity. The two modes correspond to the ground state and the first excited state of the QDs. Experiments show that the power of one mode increases, while the power of the other mode decreases as the temperature increases. The power variation between these two modes is similar to the situation of competition and anticompetition of laser modes. The physical reason is discussed in detail. © 2007 American Institute of Physics.