Electronics
| Braem BA, Gold C, Hennel S, Röösli M, Berl M, Dietsche W, Wegscheider W, Ensslin K and Ihn T (2018), "Stable branched electron flow", New Journal of Physics., July, 2018. Vol. 20(7), pp. 073015. |
BibTeX:
@article{Braem2018,
author = {Braem, B A and Gold, C and Hennel, S and Röösli, M and Berl, M and Dietsche, W and Wegscheider, W and Ensslin, K and Ihn, T},
title = {Stable branched electron flow},
journal = {New Journal of Physics},
year = {2018},
volume = {20},
number = {7},
pages = {073015},
url = {http://stacks.iop.org/1367-2630/20/i=7/a=073015?key=crossref.5547df9c234611611126c79eb433216f},
doi = {10.1088/1367-2630/aad068}
}
|
| Mattheakis M, Tsironis GP and Kaxiras E (2018), "Emergence and dynamical properties of stochastic branching in the electronic flows of disordered Dirac solids", EPL (Europhysics Letters)., June, 2018. Vol. 122(2), pp. 27003. |
| Abstract: Graphene as well as more generally Dirac solids constitute two-dimensional materials where the electronic flow is ultra-relativistic. When a Dirac solid is deposited on a different substrate surface with roughness, a local random potential develops through an inhomogeneous charge impurity distribution. This external potential affects profoundly the charge flow and induces a chaotic pattern of current branches that develops through focusing and defocusing effects produced by the randomness of the surface. An additional bias voltage may be used to tune the branching pattern of the charge carrier currents. We employ analytical and numerical techniques in order to investigate the onset and the statistical properties of carrier branches in Dirac solids. We find a specific scaling-type relationship that connects the physical scale for the occurrence of branches with the characteristic medium properties, such as disorder and bias field. We use numerics to test and verify the theoretical prediction as well as a perturbative approach that gives a clear indication of the regime of validity of the approach. This work is relevant to device applications and may be tested experimentally. |
BibTeX:
@article{Mattheakis2018,
author = {Mattheakis, Marios and Tsironis, G. P. and Kaxiras, Efthimios},
title = {Emergence and dynamical properties of stochastic branching in the electronic flows of disordered Dirac solids},
journal = {EPL (Europhysics Letters)},
year = {2018},
volume = {122},
number = {2},
pages = {27003},
note = {Publisher: IOP Publishing},
doi = {10.1209/0295-5075/122/27003}
}
|
| Liu B and Heller EJ (2013), "Stability of Branched Flow from a Quantum Point Contact", Physical Review Letters., December, 2013. Vol. 111(23), pp. 236804. |
BibTeX:
@article{Liu2013,
author = {Liu, Bo and Heller, Eric J.},
title = {Stability of Branched Flow from a Quantum Point Contact},
journal = {Physical Review Letters},
year = {2013},
volume = {111},
number = {23},
pages = {236804},
note = {00000},
doi = {10.1103/PhysRevLett.111.236804}
}
|
| Maryenko D, Ospald F, v. Klitzing K, Smet JH, Metzger JJ, Fleischmann R, Geisel T and Umansky V (2012), "How branching can change the conductance of ballistic semiconductor devices", Physical Review B., May, 2012. Vol. 85(19), pp. 195329. |
| Abstract: We demonstrate that branching of the electron flow in semiconductor nanostructures can strongly affect macroscopic transport quantities and can significantly change their dependence on external parameters compared to the ideal ballistic case, even when the system size is much smaller than the mean free path. In a corner-shaped ballistic device based on a GaAs/AlGaAs two-dimensional electron gas, we observe a splitting of the commensurability peaks in the magnetoresistance curve. We show that a model which includes a random disorder potential of the two-dimensional electron gas can account for the random splitting of the peaks that result from the collimation of the electron beam. The shape of the splitting depends on the particular realization of the disorder potential. At the same time, magnetic focusing peaks are largely unaffected by the disorder potential. |
BibTeX:
@article{maryenko_how_2012,
author = {Maryenko, D. and Ospald, F. and v. Klitzing, K. and Smet, J. H. and Metzger, J. J. and Fleischmann, R. and Geisel, T. and Umansky, V.},
title = {How branching can change the conductance of ballistic semiconductor devices},
journal = {Physical Review B},
year = {2012},
volume = {85},
number = {19},
pages = {195329},
doi = {10.1103/PhysRevB.85.195329}
}
|
| Jura MP, Topinka MA, Urban L, Yazdani A, Shtrikman H, Pfeiffer LN, West KW and Goldhaber-Gordon D (2007), "Unexpected features of branched flow through high-mobility two-dimensional electron gases", Nature Physics. Vol. 3(12), pp. 841-845. |
BibTeX:
@article{Jura2007,
author = {Jura, M. P. and Topinka, M. A. and Urban, L. and Yazdani, A. and Shtrikman, H. and Pfeiffer, L. N. and West, K. W. and Goldhaber-Gordon, D.},
title = {Unexpected features of branched flow through high-mobility two-dimensional electron gases},
journal = {Nature Physics},
year = {2007},
volume = {3},
number = {12},
pages = {841--845},
doi = {10.1038/nphys756}
}
|
|
LeRoy BJ (2003), "Imaging coherent electron flow", Journal of Physics Condensed Matter. Vol. 15(50), pp. 1835-1864.
[BibTeX] |
BibTeX:
@article{LeRoy2003,
author = {LeRoy, B. J.},
title = {Imaging coherent electron flow},
journal = {Journal of Physics Condensed Matter},
year = {2003},
volume = {15},
number = {50},
pages = {1835--1864}
}
|
| Topinka MA, Westervelt RM and Heller EJ (2003), "Imaging electron flow", Physics Today., December, 2003. Vol. 56(12), pp. 47-52. |
| Abstract: New scanning probe techniques provide fascinating glimpses into the detailed behavior of semiconductor devices in the quantum regime. |
BibTeX:
@article{Topinka2003,
author = {Topinka, Mark A. and Westervelt, Robert M. and Heller, Eric J.},
title = {Imaging electron flow},
journal = {Physics Today},
year = {2003},
volume = {56},
number = {12},
pages = {47--52},
note = {00049},
doi = {10.1063/1.1650228}
}
|
| Topinka MA, LeRoy BJ, Westervelt RM, Shaw SEJ, Fleischmann R, Heller EJ, Maranowski KD and Gossard AC (2001), "Coherent branched flow in a two-dimensional electron gas", Nature., March, 2001. Vol. 410(6825), pp. 183-186. |
| Abstract: Semiconductor nanostructures based on two-dimensional electron gases (2DEGs) could form the basis of future devices for sensing, information processing and quantum computation. Although electron transport in 2DEG nanostructures has been well studied, and many remarkable phenomena have already been discovered (for example, weak localization, quantum chaos, universal conductance fluctuations), fundamental aspects of the electron flow through these structures have so far not been clarified. However, it has recently become possible to image current directly through 2DEG devices using scanning probe microscope techniques. Here, we use such a technique to observe electron flow through a narrow constriction in a 2DEG—a quantum point contact. The images show that the electron flow from the point contact forms narrow, branching strands instead of smoothly spreading fans. Our theoretical study of this flow indicates that this branching of current flux is due to focusing of the electron paths by ripples in the background potential. The strands are decorated by interference fringes separated by half the Fermi wavelength, indicating the persistence of quantum mechanical phase coherence in the electron flow. These findings may have important implications for a better understanding of electron transport in 2DEGs and for the design of future nanostructure devices. |
BibTeX:
@article{topinka_coherent_2001,
author = {Topinka, M. A. and LeRoy, B. J. and Westervelt, R. M. and Shaw, S. E. J. and Fleischmann, R. and Heller, E. J. and Maranowski, K. D. and Gossard, A. C.},
title = {Coherent branched flow in a two-dimensional electron gas},
journal = {Nature},
year = {2001},
volume = {410},
number = {6825},
pages = {183--186},
doi = {10.1038/35065553}
}
|
