Hall effect fractional

Shibata N, Nomura K (2009) Fractional quantum Hall effects of graphene and its bilayer. J Phys Soc Jpn 78 104708/1-104708/7... 

New physics such as the fractional quantum Hall effect has emerged from non-magnetic semiconductor heterostructures. These systems have also been a test bench for a number of new device concepts, among which are quantum well lasers and high electron mobility transistors. Ferromagnetic 111-Vs can add a new dimension to the III-V heterostructure systems because they can introduce magnetic cooperative phenomena that were not present in the conventional III-V materials. 

Eisensicin. J.F. and H.l. Siomtcr The Fractional Quantum Hall Effect. Senna. 1510 (June 2. I99l)i. 

CTiakaraborty, T. and P. Pietilainen. The Fractional Quantum Hall Effect, Spiingei-Vedag, New York, NY, 1G88. 

Laughlin, R.B. The Relationship Between High-Temperature Superconductivity and die Fractional Quantum Hall Effect, 5 Science, 525 (October 28, 1988). 

The theory above has been applied in a variety of realistic situations. The range includes ionic conductance in aqueous solutions and molten alkali chlorides, damped spin-wave behaviour in paramagnetic systems, stimulated emission of radiation in masers, the fractional quantum Hall effect and quantum correlations in high-Tc cuprates and other non-BCS superconductors [4, 5, 7, 8, 14, 30]. In the next section we will also make some comments on the problem of long-range transcorrelations of protons in DNA [31]. 

E.J. Brandas, Quantum Correlations and Topological Quantum Numbers in the Fractional Quantum Hall Effect, Ber. Bunsenges. Phys. Chem. 96 (1992) 49. 

However, in the preceding two decades, there have been many experimental discoveries, beside high-Tc superconductivity, evidencing that we do not have yet the proper theoretical skills and tools to deal well with strongly correlated electron systems. For instance, heavy-fermions, fractional quantum Hall effect, ladder materials, and very specially high-Tc superconductivity seem not accessible from the weak coupling limit. 

There is also an integer or fractional quantum Hall effect, whereby in... 

Here p is either integer (p = 1,2,3, etc.) for the integer quantum Hall effect, first measured by von Klitzing25 at cryogenic temperatures [14], or a rational fraction (p 1 /3, 1/5, 5/2, etc.) for the fractional quantum Hall effect, first measured by Tsui, Stormer, and Laughlin [15]. The very well measured quantity ez/h = 25.81280745 kQ is called the von Klitzing constant, although it should also be called Landauer s constant. 

The integer quantum Hall effect can be understood in terms of noninteracting electrons, whereas the fractional effect is thought to result from many-electron interactions in two-dimensional systems, and to be an example of anyons see quantum statistics). 

In two-space dimensions, it is possible that there are particles (or quasiparticles) that have statistics intermediate between bosons and fermions. These particles are known as anyons for identical anyons the pgK wave function is not symmetric (a phase sign of-fl) or antisymmetric (a phase signof-1), but interpolates continuously between +1 and-l.y myons maybe involved in the fractional quantum Hall effect. 

Moore, R. and Read, N., Nonabelions in the fractional quantum hall effect, Nucl. Phys. B, 360,362, 1991. 

Much of the interest in graphene centers on the fact that it is the best conductor of heat and electricity known. Electrons travel through graphene at ultrafast speeds. In fact, electrons in graphene exhibit the fractional quantum Hall effect The electrons act collectively as if they are particles with only a fraction of the charge of an electron. Because of its exceptional thermal and electrical conductivities, graphene appears to be an ideal candidate for future electronic devices. Scientists at IBM have already built graphene-based transistors that can switch on and off 26 billion times per second, far faster than conventional silicon-based devices. 

It has already been observed that spin-charge inversion is one of the remarkable features of a conjugational defect in poly acetylene charged defects are spinless neutral defects carry a magnetic moment. This inversion is related to fractionized charges, which also occur in elementary-particle physics and in the fractionized quantum Hall effect [107]. Spin-charge inversion is a symmetry property of the system, it makes use of the quasi-particle concept, but non-dispersive motion is not essential in this respect. 

O. Stem, D. Dini, N. Freytag, W. Dietsche, K. von Klitzing and W. Weg-scheider, A Study of the Domain Structure at the Spin Transition of the Fractional Quantum Hall Effect , Phys. Status Solidi, B, 2008, 245, 428. 

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