Spontaneous shape distortion in quench-condensed bismuth clusters below 8 K.
نویسندگان
چکیده
We study single-electron transport in quench-condensed bismuth films. By lateral confinement, we select a specific cluster of about 10(3) atoms and use tunneling barriers that appear naturally during thin-film formation. A remarkable reversible increase of the sample conductance up to 5 times was found as the temperature was lowered from 11 to 4 K. We attribute this effect to a spontaneous distortion of the cluster shape and discuss its relation to a phase transition predicted for free metallic clusters.
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عنوان ژورنال:
- Physical review letters
دوره 84 25 شماره
صفحات -
تاریخ انتشار 2000