Molecular photons interfaced with alkali atoms.
Future quantum communication will rely on the integration of single-photon sources, quantum memories and systems with strong single-photon nonlinearities. Two key parameters are crucial for the single-photon source: a high photon flux with a very small bandwidth, and a spectral match to other components of the system. Atoms or ions may act as single-photon sources--owing to their narrowband emission and their intrinsic spectral match to other atomic systems--and can serve as quantum nonlinear elements. Unfortunately, their emission rates are still limited, even for highly efficient cavity designs. Single solid-state emitters such as single organic dye molecules are significantly brighter and allow for narrowband photons; they have shown potential in a variety of quantum optical experiments but have yet to be interfaced with other components such as stationary memory qubits. Here we describe the optical interaction between Fourier-limited photons from a single organic molecule and atomic alkali vapours, which can constitute an efficient quantum memory. Single-photon emission rates reach up to several hundred thousand counts per second and show a high spectral brightness of 30,000 detectable photons per second per megahertz of bandwidth. The molecular emission is robust and we demonstrate perfect tuning to the spectral transitions of the sodium D line and efficient filtering, even for emitters at ambient conditions. In addition, we achieve storage of molecular photons originating from a single dibenzanthanthrene molecule in atomic sodium vapour. Given the large set of molecular emission lines matching to atomic transitions, our results enable the combination of almost ideal single-photon sources with various atomic vapours, such that experiments with giant single-photon nonlinearities, mediated, for example, by Rydberg atoms, become feasible.
3. Physikalisches Institut, Universität Stuttgart, Stuttgart Research Center of Photonic Engineering (SCoPE), and the Center for Integrated Quantum Science and Technology (IQST), Pfaffenwaldring 57, 70569 Stuttgart, Germany.
Petr
P
Siyushev
3. Physikalisches Institut, Universität Stuttgart, Stuttgart Research Center of Photonic Engineering (SCoPE), and the Center for Integrated Quantum Science and Technology (IQST), Pfaffenwaldring 57, 70569 Stuttgart, Germany.
Guilherme
G
Stein
1] 3. Physikalisches Institut, Universität Stuttgart, Stuttgart Research Center of Photonic Engineering (SCoPE), and the Center for Integrated Quantum Science and Technology (IQST), Pfaffenwaldring 57, 70569 Stuttgart, Germany [2] Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany.
Jörg
J
Wrachtrup
1] 3. Physikalisches Institut, Universität Stuttgart, Stuttgart Research Center of Photonic Engineering (SCoPE), and the Center for Integrated Quantum Science and Technology (IQST), Pfaffenwaldring 57, 70569 Stuttgart, Germany [2] Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany.
Ilja
I
Gerhardt