One-dimensional transport and the quantisation of the ballistic resistance

Although devices working on quantum principles can revolutionize the electronic industry, they have not been achieved yet as it is difficult to control their stability. We show that one can use evanescent modes to build stable quantum switches. The physical principles that make this possible is explained in detail. Demonstrations are given using a multichannel Aharonov -Bohm interferometer. We propose a new S matrix for multichannel junctions to solve the scattering problem.

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“…In the leads we can not have evanescent modes 21,22 . Now for the region II and region III the potential is V (x, y) = V (y) + V 0 .…”

Section: Theoretical Analysismentioning

confidence: 99%

“…Depending on the choice of energy E and potential V 0 , q 1 and q 2 can be real (propagating mode) as well as imaginary (evanescent mode). Such evanescent states can always be excited in the internal regions of the system but not in leads 21,22 .…”

Section: Theoretical Analysismentioning

confidence: 99%

Stable switch action based on quantum interference effect

Mukherjee

Yadav

Deo

2013

Physica E: Low-dimensional Systems and Nanostructures

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“…A notable quantum-mechanical system is a ballistic quantum wire called a quantum point contact (QPC) when it is short, and it is defined using a pair of split gates [18][19][20] on a semiconductor heterostructure. Soon after the first observation of quantized conductance in a quasi-one-dimensional (1D) quantum wire [19,20], a number of interesting observations have been made such as the "0.7 structure" [21], incipient Wigner lattice [22,23], coherent electron focusing [24][25][26], etc.…”

Section: Introductionmentioning

confidence: 99%

Interference Effects in a Tunable Quantum Point Contact Integrated with an Electronic Cavity

et al. 2017

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We show experimentally how quantum interference can be produced using an integrated quantum system comprising an arch-shaped short quantum wire (or quantum point contact, QPC) of 1D electrons and a reflector forming an electronic cavity. On tuning the coupling between the QPC and the electronic cavity, fine oscillations are observed when the arch QPC is operated in the quasi-1D regime. These oscillations correspond to interference between the 1D states and a state which is similar to the Fabry-Perot state and suppressed by a small transverse magnetic field of AE60 mT. Tuning the reflector, we find a peak in resistance which follows the behavior expected for a Fano resonance. We suggest that this is an interesting example of a Fano resonance in an open system which corresponds to interference at or near the Ohmic contacts due to a directly propagating, reflected discrete path and the continuum states of the cavity corresponding to multiple scattering. Remarkably, the Fano factor shows an oscillatory behavior taking peaks for each fine oscillation, thus, confirming coupling between the discrete and continuum states. The results indicate that such a simple quantum device can be used as building blocks to create more complex integrated quantum circuits for possible applications ranging from quantum-information processing to realizing the fundamentals of complex quantum systems.

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“…The experimental observation of conductance quantization in semiconductor point contacts [1,2] was one of the most important manifestations of quantum mechanics in mesoscopic systems. The measurement of integer numbers of a quantum of conductance (G 0 = 2e 2 /h) is a consequence of the current equipartition in a small number of propagating modes [3].…”

Section: Introductionmentioning

confidence: 99%

Conductance of three-dimensional cross junctions in the quantum ballistic regime

Dacal¹,

Silva

2006

Braz. J. Phys.

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The influence of dimensionality on the conductance of semiconductor cross junctions is investigated in the effective mass approximation and quantum ballistic regime. Our calculations exhibit some similar features for both two-and three-dimensional models, namely the conductance peaks before the fundamental eigenenergy of the quantum wire that represents the sidearms and the zero conductance dip. Despite this, we show that, in general, the conductance and the electronic wave function are strongly affected when the third spatial dimension is taken into account. In other words, we prove that two-dimensional models are not suitable for representing this kind of system.

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One-dimensional transport and the quantisation of the ballistic resistance

Cited by 2,015 publications

References 5 publications

Stable switch action based on quantum interference effect

Stable switch action based on quantum interference effect

Interference Effects in a Tunable Quantum Point Contact Integrated with an Electronic Cavity

Conductance of three-dimensional cross junctions in the quantum ballistic regime

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