High resolution imaging of graphene by tip enhanced coherent anti Stokes Raman s

Coherent anti-Stokes Raman scattering (CARS) is able to enhance molecular signals by vibrational coherence compared to weak Raman signal. The surface or tip enhancement are successful technologies, which make it possible for Raman to detect single molecule with nanometer resolution. However, due to technical difficulties, tip-enhanced CARS (TECARS) is not as successful as expected. For single molecular detection, high sensitivity and resolution are two main challenges. Here, we reported the firs