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## Temperature evolution of two-state lasing in microdisk lasers with InAs/InGaAs quantum dots

One-state and two-state lasing is investigated experimentally and through numerical simulation

as a function of temperature in microdisk lasers with Stranski–Krastanow InAs/InGaAs/GaAs

quantum dots. Near room temperature, the temperature-induced increment of the ground-state

threshold current density is relatively weak and can be described by a characteristic temperature

of about 150 K. At elevated temperatures, a faster (super-exponential) increase in the threshold

current density is observed. Meanwhile, the current density corresponding to the onset of two-state

lasing was found to decrease with increasing temperature, so that the interval of current density

of pure one-state lasing becomes narrower with the temperature increase. Above a certain critical

temperature, ground-state lasing completely disappears. This critical temperature drops from 107

to 37 C as the microdisk diameter decreases from 28 to 20 um. In microdisks with a diameter of

9 um, a temperature-induced jump in the lasing wavelength from the first excited-state to second

excited-state optical transition is observed. A model describing the system of rate equations and free

carrier absorption dependent on the reservoir population provides a satisfactory agreement with

experimental results. The temperature and threshold current corresponding to the quenching of

ground-state lasing can be well approximated by linear functions of saturated gain and output loss.