摘要
High-performance solid-state quantum sources in the telecom band are of paramount importance for longdistance quantum communications and the quantum Internet by taking advantage of a low-loss optical fiber network.Here,we demonstrate bright telecom-wavelength single-photon sources based on In(Ga)As/Ga As quantum dots(QDs)deterministically coupled to hybrid circular Bragg resonators(h-CBRs)by using a wide-field fluorescence imaging technique.The QD emissions are redshifted toward the telecom O-band by using an ultra-low In As growth rate and an In Ga As strain reducing layer.Single-photon emissions under both continuous wave(CW)and pulsed operations are demonstrated,showing high brightness with count rates of 1.14 MHz and 0.34 MHz under saturation powers and single-photon purities of g^(2)(0)=0.11±0.02(CW)and g^(2)(0)=0.087±0.003(pulsed)at low excitation powers.A Purcell factor of 4.2 with a collection efficiency of 11.2%±1%at the first lens is extracted,suggesting efficient coupling between the QD and h-CBR.Our work contributes to the development of highly efficient single-photon sources in the telecom band for fiber-based quantum communication and future distributed quantum networks.
基金
National Key Research and Development Program of China(2018YFA0306103)
Special Project for Research and Development in Key areas of Guangdong Province(2018B030329001)
National Natural Science Foundation of China(11874437,12074442,62035017,91836303)
Guangdong Special Support Plan(2019JC05X397)。
