Atomic manipulation technique

 

IBM scientists first to image the anatomy of a molecule

Technique

Imaging the structure of molecules with atomic resolution was achieved by noncontact atomic force microscopy (NC-AFM). Our low-temperature STM/AFM is based on a qPlus sensor design [1] and is operated in an ultrahigh vacuum at a temperature of 5 K.

The key step to achieving atomic resolution on molecules is the functionalization of the microscope’s tip apex with a suitable, atomically well-defined termination, such as a CO molecule [2]. In this case, atomic manipulation techniques are essential for the controlled buildup of the tip used for AFM imaging [3].

We also perform density functional theory (DFT) calculations to elucidate the physical origins of the contrast observed. The calculations reveal that the Pauli repulsion is the source of the atomic resolution [2] and yield insights into the important role of the tip functionalization [4].


References

[1] F. J. Giessibl, Appl. Phys. Lett. 73, 3956 (1998).

[2] L. Gross, F. Mohn, N. Moll, P. Liljeroth, G. Meyer, Science 325, 1110 (2009).
Abstract | Full text

[3] F. Mohn, B. Schuler, L. Gross, G. Meyer, Appl. Phys. Lett., 102, 073109 (2013).

[4] L. Gross, F. Mohn, N. Moll, B. Schuler, A. Criado, E. Guitian, D. Peña, A. Gourdon, G. Meyer, Science 337, 1326 (2012).

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Leo Gross

Leo Gross

IBM Research scientist

Gerhard Meyer

Gerhard Meyer

IBM Research scientist