Finite-frequency noise in a quantum point contact between helical edge states
نویسندگان
چکیده
منابع مشابه
Experimental test of the high-frequency quantum shot noise theory in a quantum point contact.
We report on direct measurements of the electronic shot noise of a quantum point contact at frequencies nu in the range 4-8 GHz. The very small energy scale used ensures energy independent transmissions of the few transmitted electronic modes and their accurate knowledge. Both the thermal energy and the quantum point contact drain-source voltage V_{ds} are comparable to the photon energy hnu le...
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The hallmark of the spin-Hall insulator is the presence of gapless edge states of different spins moving in opposite directions. Through analytical solutions in a model calculation for a strip of finite width, we find that edge states on the two sides can couple together to produce a gap in the spectrum, destroying the quantum spin-Hall effect. The application of a magnetic field can however mo...
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Reznikov et al. [Phys. Rev. Lett. 75, 3340 (1995)]] have presented definitive observations of nonequilibrium noise in a quantum point contact. Especially puzzling is the "anomalous" peak structure of the excess noise measured at constant current; to date it remains unexplained. We show that their experiment directly reveals the deep link between conservation principles in the electron gas and i...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2012
ISSN: 1098-0121,1550-235X
DOI: 10.1103/physrevb.86.161410