Quantum information science has the potential to significantly improve our modern technologies. In this rapid-growing field, the common ability to encode, communicate and manipulate quantum bits are the necessary condition on the roadmap towards the development of quantum technologies. Due to their weak coupling with the environment, photons can be used as the so-called flying qubits, carrying the quantum information within a device or in between two nodes of a larger-scale quantum network.
As quantum science is developing toward technologies, it is essential to have practical and scalable photon sources that can operate well, outside of laboratories. Until now, it has been particularly demanding to meet the requirement of, simultaneously, having a source emitting a high rate of indistinguishable Fourier-transform limited single photons with wavelengths and linewidths matching those of matter qubits, while being compact and easy to use (= no cooling, no complex system). The current proposal aims at developing a practical atom-based, source of non-classical light devoid of cooling system or ultra-high vacuum. Based on a novel theoretical proposal, our source can generate narrow linewidth in a thermal atomic vapor.