Novel Differential Conductance Oscillations in Asymmetric Quantum Point   Contacts
  Small differential conductance oscillations as a function of source-drain bias were observed and systematically studied in an asymmetric quantum point contact (QPC). These oscillations become significantly suppressed in a small in-plane magnetic field ($\sim~0.7~T$) or at higher temperatures ($\sim~800~mK$). Qualitatively, their temperature evolution can be simulated numerically based on smearing of the Fermi distribution, whereas features near zero-bias cannot. Single particle scenarios are unsatisfactory in accounting for the oscillations, suggesting that they are likely caused by electron and spin correlation effects. 
Hao Zhang, Phillip M. Wu, Albert M. Chang
cond-mat.mes-hall