Ratchet effect in mesoscopic systems

İnkaya, Uğur Yiğit
Rectification phenomena in two specific mesoscopic systems are reviewed. The phenomenon is called ratchet effect, and such systems are called ratchets. In this thesis, particularly a rocked quantum-dot ratchet, and a tunneling ratchet are considered. The origin of the name is explained in a brief historical background. Due to rectification, there is a net non-vanishing electronic current, whose direction can be reversed by changing rocking amplitude, the Fermi energy, or applying magnetic field to the devices (for the rocked ratchet), and tuning the temperature (for the tunneling ratchet). In the last part, a theoretical examination based on the Landauer-Büttiker formalism of mesoscopic quantum transport is presented.


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Citation Formats
U. Y. İnkaya, “Ratchet effect in mesoscopic systems,” M.S. - Master of Science, Middle East Technical University, 2005.