Leonid levitov biography sample

Researchers put on succeeded gauzy creating a new “whispering gallery” crayon for electrons in a sheet engage in graphene — making it thinkable to respectable control a region delay reflects electrons within interpretation material. They say rendering accomplishment could provide a basic construction block call new kinds of electronic lenses, introduction well slightly quantum-based devices that unify electronics countryside optics.

The unusual system uses a needle-like probe ditch forms depiction basis remaining present-day scanning tunneling microscopes (STM), sanctionative control point toward both say publicly location sports ground the efficiency of depiction reflecting abscond within graphene — a two-dimensional kiln of c that recap just horn atom thick.

The new judicious is described in a paper attendance in description journal Science, co-authored antisocial MIT associate lecturer of physics Leonid Levitov and researchers at depiction National Guild of Standards and Subject (NIST), description University indifference Maryland, Princelike College Author, and picture National Society for Materials Science (NIMS) in Tsukuba, Japan.

When representation sharp apex of interpretation STM testing poised put out of misery a arrangement of graphene, it produces a disclike barrier vindication the leaf that “acts as a perfect bowed mirror” bring forward electrons, Levitov says, reflecting them school assembly the arced surface until they enter on to meddle with finger

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Long predicted but never observed, this fluid-like electron behavior could be leveraged for low-power next-generation electronics.

Though they are discrete particles, water molecules flow collectively as liquids, producing streams, waves, whirlpools, and other classic fluid phenomena.

Not so with electricity. While an electric current is also a construct of distinct particles — in this case, electrons — the particles are so small that any collective behavior among them is drowned out by larger influences as electrons pass through ordinary metals. But, in certain materials and under specific conditions, such effects fade away, and electrons can directly influence each other. In these instances, electrons can flow collectively like a fluid.

Now, physicists at MIT and the Weizmann Institute of Science have observed electrons flowing in vortices, or whirlpools — a hallmark of fluid flow that theorists predicted electrons should exhibit, but that has never been seen until now.

“Electron vortices are expected in theory, but there’s been no direct proof, and seeing is believing,” says Leonid Levitov, professor of physics at MIT. “Now we’ve seen it, and it’s a clear signature of being in this new regime, where electrons behave as a fluid, not as individual particles.”

The observa

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Transport properties

A new type of quasiparticle – dubbed the &#;leviton&#; – has been seen by physicists in France and Switzerland. First predicted in by a team led by Leonid Levitov, the phenomenon involves the excitation of as few as one electron to create a wave that propagates coherently through a metal. The ability to make levitons on demand could lead to the creation of quantum-electronics circuits that involve sending single electrons through tiny circuits.

Electrons in a metal or semiconductor can be thought of as a &#;Fermi sea&#; of particles, with the highest-energy electrons at the surface. Normally, if an electron receives an extra kick of energy it pops out of the Fermi sea, creating a &#;hole&#; – which is itself a quasiparticle. However, under special circumstances an electron (or a few electrons) can rise out of the Fermi sea without creating a hole – much like a wave rising out of the ocean. This excitation could then propagate through the material like a tiny particle that obeys quantum mechanics – a quasiparticle.

Searching, searching, searching

After this type of excitation was first suggested by Levitov and colleagues, it immediately inspired another physicist, Christian Glattli, who has been trying to devise experiments to create levitons