title: Coherent emission from integrated Talbot-cavity quantum cascade lasers.
abstract: We report experimental realization of phase-locked quantum cascade laser (QCL) array using a monolithically integrated Talbot cavity. An array with six laser elements at a wavelength of ~4.8 μm shows a maximum peak power of ~4 W which is more than 5 times higher than that of a single ridge laser element and a slope efficiency of 1 W/A at room temperature. Operation of in-phase coherent supermode has been achieved over the whole dynamic range of the Talbot-cavity QCL. The structure was analysed using a straightforward theoretical model, showing quantitatively good agreement with the experimental results. The reduced thermal resistance makes the structure an attractive approach to achieve high beam quality continuous wave QCLs.
authors.forename: Bo
authors.initials: B
authors.lastname: Meng
authors.forename: Bo
authors.initials: B
authors.lastname: Qiang
authors.forename: Etienne
authors.initials: E
authors.lastname: Rodriguez
authors.forename: Xiao Nan
authors.initials: XN
authors.lastname: Hu
authors.forename: Guozhen
authors.initials: G
authors.lastname: Liang
authors.forename: Qi Jie
authors.initials: QJ
authors.lastname: Wang