• Corpus ID: 117942935

Persistence of the 0.7 anomaly of quantum point contacts in high magnetic fields

  title={Persistence of the 0.7 anomaly of quantum point contacts in high magnetic fields},
  author={E. J. Koop and Alexandru Ionut Lerescu and J. D. Liu and Bart Jan van Wees and Dirk Reuter and Andreas Dirk Wieck and Caspar H. van der Wal},
  journal={arXiv: Mesoscale and Nanoscale Physics},
The spin degeneracy of the lowest subband that carries one-dimensional electron transport in quantum point contacts appears to be spontaneously lifted in zero magnetic field due to a phenomenon that is known as the 0.7 anomaly. We measured this energy splitting, and studied how it evolves into a splitting that is the sum of the Zeeman effect and a field-independent exchange contribution when applying a magnetic field. While this exchange contribution shows sample-to-sample fluctuations, it is… 
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