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arXiv · 1706.08478

Artifact Free Transient Near-Field Nanoscopy

Aaron Sternbach·James Hinton·Tetiana Slusar·Alexander Swinton McLeod·Mengkun Liu·Alex Frenzel·Martin Wagner·Ruben Iraheta·Fritz Keilmann·Alfred Leitenstorfer·Michael Fogler·Hyun-Tak Kim·Richard Averitt·Dimitri Basov
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Abstract

We report on the first implementation of ultrafast near field nanoscopy carried out with the transient pseudoheterodyne detection method (Tr-pHD). This method is well suited for efficient and artifact free pump-probe scattering-type near-field optical microscopy with nanometer scale resolution. The Tr-pHD technique is critically compared to other data acquisition methods and found to offer significant advantages. Experimental evidence for the advantages of Tr-pHD is provided in the Near-IR frequency range. Crucial factors involved in achieving proper performance of the Tr-pHD method with pulsed laser sources are analyzed and detailed in this work. We applied this novel method to time-resolved and spatially resolved studies of the photo-induced effects in the insulator-to-metal transition system vanadium dioxide with nanometer scale resolution.

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Aaron Sternbach, James Hinton, Tetiana Slusar, Alexander Swinton McLeod, Mengkun Liu, Alex Frenzel, Martin Wagner, Ruben Iraheta, Fritz Keilmann, Alfred Leitenstorfer, Michael Fogler, Hyun-Tak Kim, Richard Averitt, Dimitri Basov. 2017-07-12. Artifact Free Transient Near-Field Nanoscopy. https://arxiv.org/abs/1706.08478

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