Nonlinear Propagation Theory for Few-to-Mono Optical-Cycle Pulses beyond the Slowly-Varying-Envelope Approximation (SVEA) -- Generation of Ultrabroadband Optical Pulses -- Active Chirp Compensation for Ultrabroadband Optical Pulses -- Amplitude and Phase Characterization of Few-to-Mono Optical-Cycle Pulses -- Feedback Field Control for Optical Pulse Generation in the Monocycle Region -- Field Manipulation of Ultrabroadband Optical Pulses -- Fundamental of Laser-Assisted Scanning Tunneling Microscopy (STM) -- Spatially-Resolved Surface Photovoltage Measurement -- Atomic-Level Surface Phenomena Controlled by Femtosecond Optical Pulses -- Femtosecond-Time-Resolved Scanning Tunneling Microscopy -- Outlook."Mono-Cycle Photonics and Optical Scanning Tunneling Microscopy" deals with both the ultrashort laser-pulse technology in the few- to mono-cycle region and the laser-surface-controlled scanning-tunneling microscopy (STM) extending into the spatiotemporal extreme technology. The former covers the theory of nonlinear pulse propagation beyond the slowly-varing-envelope approximation, the generation and active chirp compensation of ultrabroadband optical pulses, the amplitude and phase characterization of few- to mono-cycle pulses, and the feedback field control for the mono-cycle-like pulse generation. In addition, the wavelength-multiplex shaping of ultrabroadband pulse is described. The latter covers the CW-laser-excitation STM, the femtosecond-time-resolved STM and atomic-level surface phenomena controlled by femtosecond pulses.