Emergent Quantum Phenomena


1980 Klaus von Klitzing discovered the Quantized Hall Effect

1982 Horst L. Störmer and Daniel C. Tsui discovered the Fractional Quantum Hall Effect

ar of the discovery Robert B. Laughlin had succeeded in explaining their result.

1983 Robert B Laughling formulated the theory of fractional quantum Hall effect

   In 1980, German physicist K. von Klitzing and other researchers found that the Hall conductance of two-dimensional electron gas exhibits a quantized platform structure in the unit of the basic constant e2 / h under a low temperature and strong magnetic field. When these platforms appear, the resistance of the system is zero and there is no dissipation. This is the quantum Hall effect, which is a very beautiful phenomenon of electronic collective cooperation. In 1982, physicist Chee Tsui and others further found that Hall conductivity platforms appear not only at integer multiples of e2 / h, but also at 1/3 of e2 / h or other fractional values in the two-dimensional electron gas with higher mobility, producing a fractional quantum Hall effect. The quantum Hall effect is entirely the result of the correlation effect between electrons. American physicist R. B. Laughlin did a ground-breaking work on his microscopic theoretical research.


   In 2002, another discovery was made in two-dimensional electron gas. Using GaAs/AlGaAs heterojunction samples with very high mobility, two experimental groups in Germany and the United States found that under moderate microwave irradiation, the magnetic resistance oscillated strongly with the magnetic field, and the maximum amplitude can be more than ten times that of the non-irradiation resistance, while the minimum value is almost zero in a fairly wide magnetic field range in the measurement range. However, the lateral Hall resistance is almost unchanged, and there is no sign of any quantum Hall platform. The emergence of zero resistance often foreshadows the emergence of new states of matter. Therefore, these discoveries immediately attracted widespread attention and became a hot issue in the research of low-dimensional associated electronic systems.

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