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arXiv · 0709.2615

Bulk Cr tips for scanning tunneling microscopy and spin-polarized scanning tunneling microscopy

A. Li Bassi·C. S. Casari·D. Cattaneo·F. Donati·S. Foglio·M. Passoni·C. E. Bottani·P. Biagioni·A. Brambilla·M. Finazzi·F. Ciccacci·L. Duo'
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Abstract

A simple, reliable method for preparation of bulk Cr tips for Scanning Tunneling Microscopy (STM) is proposed and its potentialities in performing high-quality and high-resolution STM and Spin Polarized-STM (SP-STM) are investigated. Cr tips show atomic resolution on ordered surfaces. Contrary to what happens with conventional W tips, rest atoms of the Si(111)-7x7 reconstruction can be routinely observed, probably due to a different electronic structure of the tip apex. SP-STM measurements of the Cr(001) surface showing magnetic contrast are reported. Our results reveal that the peculiar properties of these tips can be suited in a number of STM experimental situations.

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A. Li Bassi, C. S. Casari, D. Cattaneo, F. Donati, S. Foglio, M. Passoni, C. E. Bottani, P. Biagioni, A. Brambilla, M. Finazzi, F. Ciccacci, L. Duo'. 2007-10-29. Bulk Cr tips for scanning tunneling microscopy and spin-polarized scanning tunneling microscopy. https://doi.org/10.1063/1.2800810

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