| Autor: |
Brun, B., Martins, F., Faniel, S., Hackens, B., Bachelier, G., Cavanna, A., Ulysse, C., Ouerghi, A., Gennser, U., Mailly, D., Huant, S., Bayot, V., Sanquer, M., Sellier, H. |
| Rok vydání: |
2013 |
| Předmět: |
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| Zdroj: |
Nature Communications 5, 4290 (2014) |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1038/ncomms5290 |
| Popis: |
Quantum point contacts exhibit mysterious conductance anomalies in addition to well known conductance plateaus at multiples of 2e^2/h. These 0.7 and zero-bias anomalies have been intensively studied, but their microscopic origin in terms of many-body effects is still highly debated. Here we use the charged tip of a scanning gate microscope to tune in situ the electrostatic potential of the point contact. While sweeping the tip distance, we observe repetitive splittings of the zero-bias anomaly, correlated with simultaneous appearances of the 0.7 anomaly. We interpret this behaviour in terms of alternating equilibrium and non-equilibrium Kondo screenings of different spin states localized in the channel. These alternating Kondo effects point towards the presence of a Wigner crystal containing several charges with different parities. Indeed, simulations show that the electron density in the channel is low enough to reach one-dimensional Wigner crystallization over a size controlled by the tip position. |
| Databáze: |
arXiv |
| Externí odkaz: |
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