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A paper that discovers the quantum-critical, relativistic plasma in clean grapheme, by Assistant Professor Yang Chan Shan from the Graduate Institute of Electro-optical Science and Technology and the Physic Department of UC Berkeley was published on the latest Science.

A press conference was held on March 19th, Dean Cheng Chin Pao from the College of Science and Technology said that the College provides teacher training programs in technology education, graphic arts, electronics engineering, mechanical engineering, power and energy, and other technical education areas. Professors in this unit are have abundant research ideas. Yang, aged 32, has already published on a prestigious journal. NTNU purchased a pulse transmitter so that the professors are well equipped.

 

Assistant Professor Yang Chan Shan, Feng Wang from UC Berkeley and a PhD researcher Patrick Gallagher spent two years on this project and achieved breakthrough result. The experiment subject is about 3 square centimeter size Graphene near charge neutrality is expected to behave like a quantum-critical, relativistic plasma—the “Dirac fluid”—in which massless electrons and holes rapidly collide at a rapid rate.

 

The quantitative agreement between our experimental results and the relativistic hydrodynamic theory of the Dirac fluid imply that graphene should host relativistic phenomena not seen in typical electron systems, where relativistic hydrodynamics does not apply. For example, electronic sound waves in conventional metals either morph into plasmons or are destroyed by momentum relaxation, but such waves can exist in charge-neutral graphene owing to low disorder and zero coupling to plasmon modes. At high temperatures, graphene is also expected to display a collective cyclotron resonance that is primarily damped by collisions between charge-carriers, rather than by disorder.