Invited Symposium Selection: Ruby Anniversary Symposium to Celebrate 40 Years of GIMSInvited Speaker Selection: Wilson HoOral: Spatial Control in Atomic-Scale Excitations and the Quantum Superposition Microscope

The combination of the quantum tunneling phenomenon and precise distortions in piezoelectric materials led to the invention in 1981 of the scanning tunneling microscope (STM). In the next four decades, novel experimental methodologies beyond imaging were advanced in the detection of electronic states and inelastic electron tunneling spectroscopy (IETS) of the excitation between quantum states. The enabling technology that provided the accuracy, precision, and stability of tip positioning in the STM kept pushing back the limit of measurement and our understanding of atoms, molecules, and materials at the atomic scale. More recently, simultaneous spatial and temporal resolution has been achieved by shining femtosecond light pulses into the STM junction while preserving the ability of tip positioning and spatial resolution. Such advancement in instrument and measurement technology led to the invention of the quantum superposition microscope (QSM) based on the temporal coherence of a two-level molecular sensor for imaging the electric field of a material's surface.