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Updated: Jul 8, 2025
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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
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Probing Spin-Dependent Ballistic Charge Transport at Single-Nanometer Length Scales
Patrick Härtl1, Markus Leisegang1, Jens Kügel1
1Physikalisches Institut, Experimentelle Physik II, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
Nano Letters
|December 14, 2023
Summary
Researchers developed a new method to map spin transport in materials. This technique uses a magnetic tip and molecular probe to visualize spin-polarized currents with nanometer precision, crucial for quantum technologies.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Technologies
Background:
- Coherent charge and spin transport are essential for quantum computing and communication devices.
- Scattering at defects can degrade quantum coherence, impacting device performance.
- Experimental methods for real-space detection of ballistic spin transport with nanometer resolution are limited.
Purpose of the Study:
- To develop a novel technique for nanometer-resolution real-space detection of ballistic spin transport.
- To overcome the limitations of existing methods for assessing spin transport properties.
Main Methods:
- Utilized spin-polarized scanning tunneling microscopy (SP-STM).
- Integrated the molecular nanoprobe (MONA) technique.
- Employed local injection of spin-polarized charge carriers from a magnetic STM tip.
- Detected carriers using a single surface-deposited phthalocyanine molecule via reversible electron-induced tautomerization.
Main Results:
- Demonstrated a novel approach for detecting spin-polarized charge carrier transport.
- Successfully mapped spin transport properties with nanometer resolution.
- Observed current direction reversal upon tip magnetization reversal in BiAg2, linked to its spin-momentum-locked surface state.
Conclusions:
- The combined SP-STM and MONA technique provides a powerful new tool for characterizing spin transport.
- This method enables detailed investigation of spin coherence and scattering effects in materials.
- The findings are significant for advancing the development of quantum devices.
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