Atomic-scale spin-polarization maps using functionalized superconducting probes

A scanning tunneling microscope (STM) with a magnetic tip that has a sufficiently strong spin polarization can be used to map the sample’s spin structure down to the atomic scale but usually lacks the possibility to absolutely determine the value of the sample’s spin polarization. Magnetic impurities in superconducting materials give rise to pairs of perfectly, i.e., 100%, spin-polarized subgap resonances. In this work, we functionalize the apex of a superconducting Nb STM tip with such impurity states by attaching Fe atoms to probe the spin polarization of atom-manipulated Mn nanomagnets on a Nb(110) surface. By comparison with spin-polarized STM measurements of the same nanomagnets using Cr bulk tips, we demonstrate an extraordinary spin sensitivity and the possibility to measure the sample’s spin-polarization values close to the Fermi level quantitatively with our new functionalized probes.

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Spin-Polarized Scanning Tunneling Microscopy (SPSTM)

MRS Proceedings ◽

10.1557/proc-231-37 ◽

1991 ◽

Vol 231 ◽

Cited By ~ 4

Author(s):

R. Wiesendanger ◽

D. Buergler ◽

G. Tarrach ◽

I.V. Shvets ◽

H.-J. Guentherodt

Keyword(s):

Scanning Tunneling Microscope ◽

High Spatial Resolution ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Promising Technique ◽

Polarized Electrons ◽

Tunneling Microscope ◽

Magnetic Structures ◽

Spin Polarized

AbstractWe report on a novel promising technique for the investigation of magnetic structures at surfaces at high spatial resolution, ultimately down to the atomic scale. This technique is based on the observation of vacuum tunneling of spin-polarized electrons by means of a scanning tunneling microscope (STM). We discuss appropriate probe tips for the spin-polarized STM (SPSTM) and describe initial experimental results. We further focus on the information obtained by SPSTM. Finally, the perspectives of SPSTM will be discussed.

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Joule Heating and Spin-Transfer Torque Investigated on the Atomic Scale Using a Spin-Polarized Scanning Tunneling Microscope

Physical Review Letters ◽

10.1103/physrevlett.107.186601 ◽

2011 ◽

Vol 107 (18) ◽

Cited By ~ 26

Author(s):

S. Krause ◽

G. Herzog ◽

A. Schlenhoff ◽

A. Sonntag ◽

R. Wiesendanger

Keyword(s):

Joule Heating ◽

Scanning Tunneling Microscope ◽

Spin Transfer Torque ◽

Spin Transfer ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscope ◽

Spin Polarized

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Complex magnetism in ultra-thin films: atomic-scale spin structures and resolution by the spin-polarized scanning tunneling microscope

Applied Physics A ◽

10.1007/s003390101052 ◽

2002 ◽

Vol 75 (1) ◽

pp. 25-36 ◽

Cited By ~ 22

Author(s):

S. Heinze ◽

P. Kurz ◽

D. Wortmann ◽

G. Bihlmayer ◽

S. Blügel

Keyword(s):

Thin Films ◽

Scanning Tunneling Microscope ◽

Atomic Scale ◽

Scanning Tunneling ◽

Spin Structures ◽

Tunneling Microscope ◽

Spin Polarized

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Atomic-Scale Imaging and Modification of Spins Using a Magnetic-Sensitive Scanning Tunneling Microscope

Atomic and Nanometer-Scale Modification of Materials: Fundamentals and Applications ◽

10.1007/978-94-011-2024-1_6 ◽

1993 ◽

pp. 65-73

Author(s):

R. Wiesendanger

Keyword(s):

Scanning Tunneling Microscope ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscope

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MANIPULATION OF ATOMS AND MOLECULES FOR CONSTRUCTION OF NANOSYSTEMS: THE SCANNING TUNNELING MICROSCOPE AS AN OPERATIVE TOOL

International Journal of Nanoscience ◽

10.1142/s0219581x03001218 ◽

2003 ◽

Vol 02 (04n05) ◽

pp. 197-218

Author(s):

K.-F. BRAUN ◽

F. MORESCO ◽

K. MORGENSTERN ◽

S. FÖLSCH ◽

J. REPP ◽

...

Keyword(s):

Scanning Tunneling Microscope ◽

Single Molecules ◽

Short Review ◽

Atomic Scale ◽

Scanning Tunneling ◽

Tunneling Microscope ◽

Nanoscale Structures ◽

Constant Height ◽

Functionalized Tips ◽

Structure Research

Controlled manipulations with scanning tunneling microscope (STM) down to the scale of small molecules and single atoms allow to build molecular and atomic nanosystems, leading to the fascinating possibility of creating manmade structures on atomic scale. Here we present a short review on investigations based on atomic scale manipulation. Upon soft lateral manipulation of adsorbed species, in which only tip/particle forces are used, three different manipulation modes can be discerned: pushing, pulling and sliding. Even the manipulation of strongly bound native substrate atoms is possible. We demonstrate applications as local analytic and synthetic chemistry tools, with important consequences on surface structure research. Vertical manipulation of Xe and CO leads to improved imaging with functionalized tips. With CO deliberately transferred to the tip, we have also succeeded to perform vibrational spectroscopy on single molecules. Furthermore, we describe how we have reproduced a full chemical reaction with single molecules, whereby all basic steps, namely preparation of the reactants, diffusion and association, are induced with the STM tip. Here also field and electron current effects are employed. Finally, we have extended the manipulation techniques to large specially designed molecules by performing lateral manipulation in constant height and realizing the principle of a conformational molecular switch. Artificial nanoscale structures built in atom by atom fashion can serve as quantum laboratories for investigations of various physical properties.

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