15 May 2007
Budding physicists learn at an early age that electrical resistance
opposes the flow of charge, and is an inherently positive quantity. But
researchers from Turkey and Germany studying 2D electron gases at low
temperatures in a semiconductor now claim to have witnessed "negative
resistance". They say that the odd effect could be used to make tiny
sources of terahertz radiation, which can normally only be produced in
much larger devices such as synchrotrons (Phys. Rev. Lett.
98 186801).
Article link from Intalek site (Thx to Bill Alek)
'Negative
resistance' surprises material scientists
10 July 1998
Two US scientists claim to have discovered a new electrical effect
called negative resistance in carbon-composite materials. And when
materials exhibiting negative resistance are combined with 'normal'
materials, they appear to have zero resistance to electrical current,
similar to superconducting materials. Moreover, this behaviour persists to
room temperature, whereas "high-temperature" superconductors only lose
their resistance below about 150K or -120 C. The results were presented at
fifth International Conference on Composites Engineering in Las
Vegas.
Full text: http://physicsweb.org/articles/news/2/7/4/1
