5.3 Near-Field Scanning Optical Microscopy Combined
with Digital Holography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
5.3.1 Experimental Setup . . . . . . . . . . . . . . . . . . . . . . . . . . 121
5.3.2 3D Reconstructed EM Field Through Different
Media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
5.3.3 Characterization of the Angular Scattering . . . . . . . . . . 125
5.4 Possible Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
5.4.1 Coupled Nanoantennas . . . . . . . . . . . . . . . . . . . . . . . . 128
5.4.2 Brownian Nanoparticles as Stochastic Optical
Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
5.4.3 Scattering Through Disordered Media . . . . . . . . . . . . . 132
5.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
6 Absorption-Based Far-Field Label-Free Super-Resolution
Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Chen Li and Ji-Xin Cheng
6.1 Introduction to Absorption-Based Far-Field Label-Free
Super-Resolution Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . 137
6.2 Breaking the Diffraction Limit in IR Microscopy Through
Photothermal Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
6.2.1 Laser-Induced Photothermal Lens Effect:
The Origin of the Photothermal Contrast . . . . . . . . . . . 140
6.2.2 Improvement of Detection Sensitivity
of Photothermal Spectroscopy . . . . . . . . . . . . . . . . . . . 140
6.2.3 Beat the Diffraction Limit of the Pump Beam . . . . . . . 142
6.2.4 Visible Beam Excited Photothermal Microscopy . . . . . 146
6.2.5 Mid-IR Excited Photothermal Microscopy . . . . . . . . . . 149
6.2.6 Applications of Super-Resolution Photothermal
Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
6.3 Super-Resolution Transient Absorption Microscopy . . . . . . . . . 156
6.3.1 Transient Absorption Microscopy . . . . . . . . . . . . . . . . 157
6.3.2 Spatially Controlled Saturated Transient
Absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
6.3.3 Super-Resolution Stimulated Raman Microscopy . . . . . 161
6.4 Conclusion and Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
7 Label-Free Pump–Probe Nanoscopy . . . . . . . . . . . . . . . . . . . . . . . . 171
Paolo Bianchini, Giulia Zanini and Alberto Diaspro
7.1 Nonlinear Optical Interactions . . . . . . . . . . . . . . . . . . . . . . . . . 171
7.1.1 Nonlinear Absorption . . . . . . . . . . . . . . . . . . . . . . . . . 172
7.2 Pump–Probe Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
7.2.1 Pump–Probe Microscope Design . . . . . . . . . . . . . . . . . 175
Contents
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with Digital Holography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
5.3.1 Experimental Setup . . . . . . . . . . . . . . . . . . . . . . . . . . 121
5.3.2 3D Reconstructed EM Field Through Different
Media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
5.3.3 Characterization of the Angular Scattering . . . . . . . . . . 125
5.4 Possible Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
5.4.1 Coupled Nanoantennas . . . . . . . . . . . . . . . . . . . . . . . . 128
5.4.2 Brownian Nanoparticles as Stochastic Optical
Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
5.4.3 Scattering Through Disordered Media . . . . . . . . . . . . . 132
5.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
6 Absorption-Based Far-Field Label-Free Super-Resolution
Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Chen Li and Ji-Xin Cheng
6.1 Introduction to Absorption-Based Far-Field Label-Free
Super-Resolution Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . 137
6.2 Breaking the Diffraction Limit in IR Microscopy Through
Photothermal Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
6.2.1 Laser-Induced Photothermal Lens Effect:
The Origin of the Photothermal Contrast . . . . . . . . . . . 140
6.2.2 Improvement of Detection Sensitivity
of Photothermal Spectroscopy . . . . . . . . . . . . . . . . . . . 140
6.2.3 Beat the Diffraction Limit of the Pump Beam . . . . . . . 142
6.2.4 Visible Beam Excited Photothermal Microscopy . . . . . 146
6.2.5 Mid-IR Excited Photothermal Microscopy . . . . . . . . . . 149
6.2.6 Applications of Super-Resolution Photothermal
Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
6.3 Super-Resolution Transient Absorption Microscopy . . . . . . . . . 156
6.3.1 Transient Absorption Microscopy . . . . . . . . . . . . . . . . 157
6.3.2 Spatially Controlled Saturated Transient
Absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
6.3.3 Super-Resolution Stimulated Raman Microscopy . . . . . 161
6.4 Conclusion and Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
7 Label-Free Pump–Probe Nanoscopy . . . . . . . . . . . . . . . . . . . . . . . . 171
Paolo Bianchini, Giulia Zanini and Alberto Diaspro
7.1 Nonlinear Optical Interactions . . . . . . . . . . . . . . . . . . . . . . . . . 171
7.1.1 Nonlinear Absorption . . . . . . . . . . . . . . . . . . . . . . . . . 172
7.2 Pump–Probe Microscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
7.2.1 Pump–Probe Microscope Design . . . . . . . . . . . . . . . . . 175
Contents
xiii