Kondo Effect may help electronics to move beyond cmos

The Kondo Effect, named after Japanese physicist Jun Kondo, describes how the addition of traces of magnetic impurities to metals like gold or copper affects their properties. According to the researchers, the Effect can also be demonstrated when molecules like nitric oxide are located between metal electrodes. The team believes this could be exploited to change the conductance between two electrodes. The Kondo Effect occurs when the presence of a magnetic atom as an impurity causes the movement of electrons in a material to behave unusually. "Every electron has a mechanical or magnetic rotation moment, termed spin," said SISSA's ErioTosatti. "Kondo is a phenomenon related to the spin of metal electrons when they encounter a magnetic impurity. The free metal electrons cluster around the impurity and 'screen it' so that it can no longer be detected, at least so long as the temperature is sufficiently low." This results in changes to the specific properties of the material: for example, an increase in electrical resistance. Tosatti and Ryan Requist created a computer model of the Kondo Effect under these conditions and formulated predictions on molecular behaviour of the molecules. These were then tested experimentally. The results are said to be encouraging. According to Requist: "Our work demonstrates for the first time that we can predict the Kondo Effect quantitatively and it offers a theoretical basis for similar calculations with larger and more complex molecules. In the future it might be helpful when searching for the most appropriate molecules for these purposes." pic: Simplificamos Su Trabajo