報告題目：Tip-enhanced strong coupling: Broadband room temperature nano-cavity QED with single emitters
報 告 人：Markus B. Raschke (University of Colorado)
Optical cavities can enhance and control the light-matter interaction by modifying the local electromagnetic environment of a quantum emitter. However, large cavity mode volumes have prevented strong coupling of single emitters under ambient conditions. We demonstrate tip-enhanced strong coupling (TESC) spectroscopy, imaging, and control based on scanning probe microscopy using plasmonic antenna-tips forming a nano-cavity with the emitter . With single quantum dots we observe room temperature mode splitting up to 160 meV and anti-crossing in the energy spectra with detuning, with nanometer scale mode confinement, and atomic precision spatial control . In the extension to the infrared we achieve strong coupling of molecular vibrations through configurable optical interactions of a nanotip with an infrared resonant nanowire with hybridization and mode splitting . We observe nanotip-induced quantum interference of vibrational excitation pathways in spectroscopic nanoimaging, associated with Purcell enhancement > 106 . This work establishes a new paradigm of nano-cavity QED for coherent control of quantum states in solid state emitters and at room temperature.
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Markus Raschke is professor at the Department of Physics, Department of Chemistry, and JILA at the University of Colorado at Boulder. His research is on the development and application of new nano-scale nonlinear and ultrafast spectroscopy techniques to control the light-matter interaction on the nanoscale. These techniques allow for imaging structure and dynamics of molecular and correlated matter with nanometer spatial resolution. He received his PhD in 2000 from the Max-Planck Institute of Quantum Optics and the Technical University in Munich, Germany. Following research appointments at the University of California at Berkeley, and the Max-Born-Institute in Berlin, he became faculty member at the University of Washington in 2006, before moving with his group to Boulder in 2010. He is fellow of the Optical Society of America, the American Physical Society, and the American Association for the Advancement of Science.