Mid-infrared photothermal heterodyne imaging (MIR-PHI) techniques described herein overcome the diffraction limit of traditional MIR imaging and uses visible photodiodes as detectors. MIR-PHI experiments are shown that achieve high sensitivity, sub-diffraction limit spatial resolution, and high acquisition speed. Sensitive, affordable, and widely applicable, photothermal imaging techniques described herein can serve as a useful imaging tool for biological systems and other submicron-scale applications.

Mid-infrared photothermal heterodyne imaging (MIR-PHI) techniques described herein overcome the diffraction limit of traditional MIR imaging and uses visible photodiodes as detectors. MIR-PHI experiments are shown that achieve high sensitivity, sub-diffraction limit spatial resolution, and high acquisition speed. Sensitive, affordable, and widely applicable, photothermal imaging techniques described herein can serve as a useful imaging tool for biological systems and other submicron-scale applications.

Methods and apparatus for obtaining extremely high sensitivity chemical composition maps with spatial resolution down to a few nanometers. In some embodiments these chemical composition maps are created using a combination of three techniques: (1) Illuminating the sample with IR radiation than is tuned to an absorption band in the sample; and (2) Optimizing a mechanical coupling efficiency that is tuned to a specific target material; (3) Optimizing a resonant detection that is tuned to a specific target material. With the combination of these steps it is possible to obtain (1) Chemical composition maps based on unique IR absorption; (2) spatial resolution that is enhanced by extremely short-range tip-sample interactions; and (3) resonant amplification tuned to a specific target material. In other embodiments it is possible to take advantage of any two of these steps and still achieve a substantial improvement in spatial resolution and/or sensitivity.

Methods and apparatus for obtaining extremely high sensitivity chemical composition maps with spatial resolution down to a few nanometers. In some embodiments these chemical composition maps are created using a combination of three techniques: (1) Illuminating the sample with IR radiation than is tuned to an absorption band in the sample; and (2) Optimizing a mechanical coupling efficiency that is tuned to a specific target material; (3) Optimizing a resonant detection that is tuned to a specific target material. With the combination of these steps it is possible to obtain (1) Chemical composition maps based on unique IR absorption; (2) spatial resolution that is enhanced by extremely short-range tip-sample interactions; and (3) resonant amplification tuned to a specific target material. In other embodiments it is possible to take advantage of any two of these steps and still achieve a substantial improvement in spatial resolution and/or sensitivity.

A scanning probe microscope and method for resonance-enhanced detection using the scanning probe microscope uses a light source that is modulated in a range of frequencies to irradiate an interface between a probe tip of the microscope and a sample with modulated electromagnetic radiation from the light source. The vibrational response of the driven cantilever in response to the modulated electromagnetic radiation at the interface between the probe tip and the sample is then detected. The amplitude of the vibrational response of the cantilever over the entire range of modulation frequencies is measured to derive a photo-induced force microscope (PiFM) value.

A scanning probe microscope and method for resonance-enhanced detection using the scanning probe microscope uses a light source that is modulated in a range of frequencies to irradiate an interface between a probe tip of the microscope and a sample with modulated electromagnetic radiation from the light source. The vibrational response of the driven cantilever in response to the modulated electromagnetic radiation at the interface between the probe tip and the sample is then detected. The amplitude of the vibrational response of the cantilever over the entire range of modulation frequencies is measured to derive a photo-induced force microscope (PiFM) value.

An atomic force microscope (AFM) and method of operating the same includes a separate Z height sensor to measure, simultaneously with AFM system control, probe sample distance, pixel-by-pixel during AFM data acquisition. By mapping the AFM data to low resolution data of the Z height data, a high resolution final data image corrected for creep is generated in real time.

An atomic force microscope (AFM) and method of operating the same includes a separate Z height sensor to measure, simultaneously with AFM system control, probe sample distance, pixel-by-pixel during AFM data acquisition. By mapping the AFM data to low resolution data of the Z height data, a high resolution final data image corrected for creep is generated in real time.

A method comprises using an atomic-force microscope, acquiring a set of images associated with surfaces, and, using a machine-learning algorithm applied to the images, classifying the surfaces. As a particular example, the classification can be done in a way that relies on surface parameters derived from the images rather than using the images directly.

A method comprises using an atomic-force microscope, acquiring a set of images associated with surfaces, and, using a machine-learning algorithm applied to the images, classifying the surfaces. As a particular example, the classification can be done in a way that relies on surface parameters derived from the images rather than using the images directly.