We introduce drive-amplitude-modulation atomic force microscopy as a dynamic mode with outstanding performance in all environments from vacuum to liquids. As with frequency modulation, the new mode follows a feedback scheme with two nested loops: The first keeps the cantilever oscillation amplitude constant by regulating the driving force, and the second uses the driving force as the feedback variable for topography. Additionally, a phase-locked loop can be used as a parallel feedback allowing separation of the conservative and nonconservative interactions. We describe the basis of this mode and present some examples of its performance in three different environments. Drive-amplutide modulation is a very stable, intuitive and easy to use mode that is free of the feedback instability associated with the noncontact-to-contact transition that occurs in the frequency-modulation mode.

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cantilever oscillation amplitude phaselocked loop driveamplitudemodulation atomic force microscopy driving force noncontacttocontact transition conservative frequencymodulation mode nonconservative topography feedback instability

John Melcher,David Martínez-Martín,Miriam Jaafar,Julio Gómez-Herrero,Arvind Raman,Mariano Cuenca,.Drive-amplitude-modulation atomic force microscopy: From vacuum to liquids. 3 (1),.

John Melcher,David Martínez-Martín,Miriam Jaafar,Julio Gómez-Herrero,Arvind Raman,Mariano Cuenca,"Drive-amplitude-modulation atomic force microscopy: From vacuum to liquids" 3

John Melcher,David Martínez-Martín,Miriam Jaafar,Julio Gómez-Herrero,Arvind Raman,Mariano Cuenca,"Drive-amplitude-modulation atomic force microscopy: From vacuum to liquids"