Molecular Cavity QED

Frank Vollmer, Deshui Yu

Huang Jian, Yu-Hong Liu, Jin‐Feng Huang +1 more

Macroscopic entangled cat states not only are significant in the demonstration of the fundamentals of quantum physics, but also have wide applications in modern quantum technologies such as continuous-variable quantum information processing and quantum metrology. Here we propose a scheme for generation of macroscopic entangled cat states in a longitudinal-coupled cavity-QED model. In particular, we introduce the scheme by using the terms of a molecular cavity-QED system, which is composed of an organic molecule (including electronic and vibrational states) coupled to a single-mode cavity field. In this system, the resonance frequencies of the molecular vibration and the cavity field are modulated simultaneously, then the molecular vibrational displacement is enhanced significantly and hence macroscopic entangled cat states between the molecular vibrational mode and the cavity mode can be created. We also study quantum coherence effects in the generated states by calculating the joint Wigner function and the degree of entanglement. The dissipation effects are included by considering the state generation in the open-system case. Our results will pave the way to the study of quantum physics and quantum chemistry in molecular cavity-QED systems. The physical mechanism behind this scheme is general and can be extended to other longitudinal-coupled cavity-QED systems.

W. Lange, Q. A. Turchette, Christina J. Hood +2 more

Gerhard R. Guthöhrlein, Matthias Keller, Wolfgang Lange +2 more

Christian Lange, Arya Deepak Keni, Ishita Agarwal +6 more

We implement permanent spectral tuning to bring lifetime-limited emitters into collective resonance within an integrated photonic cavity. This addresses a fundamental challenge in solid-state cavity QED: combining multiple coherent quantum emitters with scalable nanophotonics. Our hybrid approach decouples emitter synthesis from nanophotonic fabrication using straightforward techniques that make cavity QED broadly accessible. High doping densities allow us to couple several coherent emitters to a single cavity mode, while optically-induced frequency shifting provides long-lived spectral control. By tuning two molecules into resonance, we demonstrate controlled formation of collective quantum states, establishing a scalable platform for many-body cavity QED. This opens pathways toward chemically-designed quantum systems where optical properties are engineered through synthetic chemistry.

Ullrich Martini, Axel Schenzle