Date and Time:  12-May-2023  10am

Speaker:  Dr. Nicolai Hartmann, attocube systems AG, Nanoscale Analytics, Germany

Host: Tingxiao Qin (BAQIS） 

Title:  Recent developments in optical imaging and spectroscopy with nanoscale resolution through s-SNOM

Abstract: 

This presentation will focus on recent progress in instrumentation and applications of nanoscale imaging and spectroscopy by means of scattering-type scanning optical near-field microscopy (s-SNOM). Driven by instrumentational developments in laser technology proven s-SNOM investigations such as polariton mapping, local electric field mapping in plasmonic structures and chemical identification of organic and inorganic materials can be extended to new wavelength regimes, enhancing imaging and spectroscopy capabilities, and reaching new materials. These s-SNOM based investigations often benefit from correlation with additional sample information gathered within the same instrument such as Kelvin probe force microscopy, photocurrent mapping or synchronized electrical sample contacts.

Due to the sensitivity of s-SNOM to local dielectric properties carrier profiling can be conducted in the mid-IR and THz wavelength regime with high spatial resolution. When utilizing synchronized laser setups these studies can also be carried out in pump-probe configurations to study the dynamic carrier behavior such as in classical semiconductor structures but also novel 2D materials.

About the Speaker:

Dr. Nicolai Hartmann studied Chemistry at the Ludwig-Maximilians-Universitat (LMU) in Munich, Germany and received his PhD in Physical Chemistry in the group of Prof. Dr. Achim Hartschuh at the LMU. Focusing on the development of new confocal and near-field optical microscopy techniques, to study the interaction of surface plasmons with different emitter systems. From 2014 – 2016 he worked as a postdoctoral research associate in the Center for Integrated Nanotechnologies at the Los Alamos National Laboratory, USA. In the group of Dr. Stephen Doorn he refined chemical pathways for isolation and functionalization of carbon nanotubes and carbon based materials together with their spectroscopic and microscopic characterization. In a second postdoctoral researcher position for a focus project of the German Federal Ministry of Education and Research 2016 at the LMU he optically characterized novel perovskite based solar cell materials as well as developed near-field enhanced stimulated Raman scattering techniques.He joined attocube systems AG, Nanoscale Analytics (former neaspec GmbH) in 2017 as application engineer and is now advising and consulting customers from academia and industry in China.