Second-Order Nonlinear Optical Microscopy of a H–Si(111)1 × 1 Surface in Ultra-High Vacuum Conditions

Figure 6

(a) A schematic illustration of three areas on a Si(111) surface irradiated by di-IR light pulses with energy from 11 to 13 mJ/pulse. Each ring pattern represents one laser beam spot, and a total of 10 light pulses were injected into each area. (b) and (c) show SFG intensity images of a H–Si(111) surface after irradiation by di-IR light pulses with IR probe light wavenumbers of 1954 cm⁻¹ and 2084 cm⁻¹, respectively. The bright dots represent the observed SFG photons. Scale bars are 100 μm.

(a)

(b)

(c)