Cavity electrodynamics offers a unique avenue for tailoring ground-state material properties,excited-state engineering,and versatile control of quantum matter.Merging these concepts with high-field physics in the tera...Cavity electrodynamics offers a unique avenue for tailoring ground-state material properties,excited-state engineering,and versatile control of quantum matter.Merging these concepts with high-field physics in the terahertz(THz)spectral range opens the door to explore low-energy,field-driven cavity electrodynamics,emerging from fundamental resonances or order parameters.Despite this demand,leveraging the full potential of field-driven material control in cavities is hindered by the lack of direct access to the intra-cavity fields.Here,we demonstrate a new concept of active cavities,consisting of electro-optic Fabry-Perot resonators,which measure their intra-cavity electric fields on sub-cycle timescales.We thereby demonstrate quantitative retrieval of the cavity modes in amplitude and phase,over a broad THz frequency range.To enable simultaneous intra-cavity sampling alongside excited-state material control,we design a tunable multi-layer cavity,enabling deterministic design of hybrid cavities for polaritonic systems.Our theoretical models reveal the origin of the avoided crossings embedded in the intricate mode dispersion,and will enable fully-switchable polaritonic effects within arbitrary materials hosted by the hybrid cavity.Electro-optic cavities(EOCs)will therefore serve as integrated probes of light-matter interactions across all coupling regimes,laying the foundation for field-resolved intra-cavity quantum electrodynamics.展开更多
基金the Emmy Noether Programme of the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation,no.469405347)Open Access funding enabled and organized by Projekt DEAL。
文摘Cavity electrodynamics offers a unique avenue for tailoring ground-state material properties,excited-state engineering,and versatile control of quantum matter.Merging these concepts with high-field physics in the terahertz(THz)spectral range opens the door to explore low-energy,field-driven cavity electrodynamics,emerging from fundamental resonances or order parameters.Despite this demand,leveraging the full potential of field-driven material control in cavities is hindered by the lack of direct access to the intra-cavity fields.Here,we demonstrate a new concept of active cavities,consisting of electro-optic Fabry-Perot resonators,which measure their intra-cavity electric fields on sub-cycle timescales.We thereby demonstrate quantitative retrieval of the cavity modes in amplitude and phase,over a broad THz frequency range.To enable simultaneous intra-cavity sampling alongside excited-state material control,we design a tunable multi-layer cavity,enabling deterministic design of hybrid cavities for polaritonic systems.Our theoretical models reveal the origin of the avoided crossings embedded in the intricate mode dispersion,and will enable fully-switchable polaritonic effects within arbitrary materials hosted by the hybrid cavity.Electro-optic cavities(EOCs)will therefore serve as integrated probes of light-matter interactions across all coupling regimes,laying the foundation for field-resolved intra-cavity quantum electrodynamics.