There is a fundamental conductance ÷ voltage limit in low voltage (less than 4kT/q) tunnel switching devices that obtain a sharp turn off by relying upon the band edges to abruptly cut off the available density of states. The Fermi occupation probabilities are thermally broadened by 4kbT. However, current is only allowed to flow in a narrow energy range limited by the applied voltage, V. This means that if we apply a voltage less than 4kbT/q, the conductance will be reduced by at least qV/4kbT. Even with a perfect tunneling probability of 1 in a perfect quantum channel, the conductance quantum would be diminished by qV/4kT. Attempts at lowering the operating voltage below 4kT/q must come at the expense of smaller conductance.
Title
Fundamental Conductance ÷ Voltage Limit in Low Voltage Tunnel Switches
Published
2013-12-31
Full Collection Name
Electrical Engineering & Computer Sciences Technical Reports
Other Identifiers
EECS-2013-247
Type
Text
Extent
4 p
Archive
The Engineering Library
Usage Statement
Researchers may make free and open use of the UC Berkeley Library’s digitized public domain materials. However, some materials in our online collections may be protected by U.S. copyright law (Title 17, U.S.C.). Use or reproduction of materials protected by copyright beyond that allowed by fair use (Title 17, U.S.C. § 107) requires permission from the copyright owners. The use or reproduction of some materials may also be restricted by terms of University of California gift or purchase agreements, privacy and publicity rights, or trademark law. Responsibility for determining rights status and permissibility of any use or reproduction rests exclusively with the researcher. To learn more or make inquiries, please see our permissions policies (https://www.lib.berkeley.edu/about/permissions-policies).
