Periodic Reporting for period 1 - DEMONS (DEterministic MOlecular N-photon Source (DEMONS))
Période du rapport: 2021-05-01 au 2023-04-30
In the MSCA-IF proposal “DEterministic MOlecular N-photon Source (DEMONS)” the goal was to create a novel quantum light source that on-demand emits a certain number (N) of light-quanta, called photons. Such novel N-photon source should emit on demand N indistinguishable photons, with high efficiency and negligible emission events with photon numbers different from N. Such highly non-classical N-photon guns would be essential for novel light sources, quantum metrology and lithography and the production of so-called NOON-states for quantum information processing. Moreover, N-photon emitters comprise the capability to be used in various applications like medical imaging.
The main objective of the proposal was to realize a high-fidelity, multiphoton quantum light source, using light–matter interactions between an optical microcavity and a controlled number of individual organic molecules. Individual so-called polycyclic aromatic hydrocarbon (PAH) molecules embedded in a crystalline matrix serve as an excellent single photon source with high photon emission rates. By embedding individual molecules into an open tuneable and laterally scannable cavity, the plan was to alter the emitter’s emission and coherence properties.
The main objective of the proposal was to realize a high-fidelity, multiphoton quantum light source, using light–matter interactions between an optical microcavity and a controlled number of individual organic molecules. Individual so-called polycyclic aromatic hydrocarbon (PAH) molecules embedded in a crystalline matrix serve as an excellent single photon source with high photon emission rates. By embedding individual molecules into an open tuneable and laterally scannable cavity, the plan was to alter the emitter’s emission and coherence properties.
Since most of the work is still in progress, I will only focus on the published results:
Recently, single molecule strong light-matter coupling at room temperature was achieved using a plasmonic nanogap cavity / antenna. These cavity/antenna structures offer a high field enhancement and small mode volume, which is required to overcome the emitter’s rapid dephasing at room temperature. Among the greatest challenges of these systems is the exact placement of the emitter inside the nanogap with high precision. Various attempts have addressed this issue using statistical strategies or self-assembly approaches. We developed and implemented a novel tipless scanning probe technique PROscan (see image) that is capable of performing mechanically robust and controllable experiments deep in the optical near-field . We utilized this device to build an open and tunable nanogap antenna, into which we can locate individual emitters with nanometer precision. The high field enhancement drastically alters the emitter's emission properties and we expect to reach a point, where the emission rate is as fast as the dephasing of the emitter. In this regime, the so-called strong light-matter coupling regime, new quantum mechanical eigenstates are formed that can be utilized for N-photon emission. Furthermore, our scanning probe device can be used to investigate novel quantum materials with nanometer precision and high stability.
The results have been published in an high-impact journal (ACS Nano 2022, 16, 12831−12839) and where presented and discussed in top-tier international conferences.
Recently, single molecule strong light-matter coupling at room temperature was achieved using a plasmonic nanogap cavity / antenna. These cavity/antenna structures offer a high field enhancement and small mode volume, which is required to overcome the emitter’s rapid dephasing at room temperature. Among the greatest challenges of these systems is the exact placement of the emitter inside the nanogap with high precision. Various attempts have addressed this issue using statistical strategies or self-assembly approaches. We developed and implemented a novel tipless scanning probe technique PROscan (see image) that is capable of performing mechanically robust and controllable experiments deep in the optical near-field . We utilized this device to build an open and tunable nanogap antenna, into which we can locate individual emitters with nanometer precision. The high field enhancement drastically alters the emitter's emission properties and we expect to reach a point, where the emission rate is as fast as the dephasing of the emitter. In this regime, the so-called strong light-matter coupling regime, new quantum mechanical eigenstates are formed that can be utilized for N-photon emission. Furthermore, our scanning probe device can be used to investigate novel quantum materials with nanometer precision and high stability.
The results have been published in an high-impact journal (ACS Nano 2022, 16, 12831−12839) and where presented and discussed in top-tier international conferences.
To achieve the main objective, we followed to different paths. In the first path, we want to utilize strong light-matter coupling between an emitter and a cavity. At the moment we are working in this direction. The second approach is to embed N molecules in an antenna structure that collects most of the emitted light from the molecules. Exploiting near-field coupling between the emitters, we want to create a reliable N-photon source. As mentioned above, these sources will be essential for quantum information processing, quantum metrology, and lithography.