Unexpected features of branched flow through high-mobility two-dimensional electron gases
arXiv:1009.3670 · doi:10.1038/nphys756
Abstract
GaAs-based two-dimensional electron gases (2DEGs) show a wealth of remarkable electronic states, and serve as the basis for fast transistors, research on electrons in nanostructures, and prototypes of quantum-computing schemes. All these uses depend on the extremely low levels of disorder in GaAs 2DEGs, with low-temperature mean free paths ranging from microns to hundreds of microns. Here we study how disorder affects the spatial structure of electron transport by imaging electron flow in three different GaAs/AlGaAs 2DEGs, whose mobilities range over an order of magnitude. As expected, electrons flow along narrow branches that we find remain straight over a distance roughly proportional to the mean free path. We also observe two unanticipated phenomena in high-mobility samples. In our highest-mobility sample we observe an almost complete absence of sharp impurity or defect scattering, indicated by the complete suppression of quantum coherent interference fringes. Also, branched flow through the chaotic potential of a high-mobility sample remains stable to significant changes to the initial conditions of injected electrons.
22 pages, 4 figures, 1 table
References in corpus (11)
- Electron transport through double quantum dots
- Evidence for an Anisotropic State of Two-Dimensional Electrons in High Landau Levels
- Coherent Branched Flow in a Two-Dimensional Electron Gas
- The microscopic nature of localization in the quantum Hall effect
- Sensitivity of Wave Field Evolution and Manifold Stability in Chaotic Systems
- Quantum dot self consistent electronic structure and the Coulomb blockade
- Spatially resolved manipulation of single electrons in quantum dots using a scanned probe
- Imaging Transport Resonances in the Quantum Hall Effect
- Imaging Electron Interferometer
- Anisotropic Disorder in High Mobility 2D Heterostructures and its Correlation to Electron Transport
- Uniform semiclassical wave function for coherent 2D electron flow
Cited by in corpus (63)
- What lurks below the last plateau: Experimental studies of the 0.7 x 2e^2/h conductance anomaly in one-dimensional systems
- Spatially resolved study of backscattering in the quantum spin Hall state
- On the imaging of electron transport in semiconductor quantum structures by scanning-gate microscopy: successes and limitations
- A Two-dimensional Dirac fermion microscope
- Recent Experimental Progress of Fractional Quantum Hall Effect: 5/2 Filling State and Graphene
- Wigner and Kondo physics in quantum point contacts revealed by scanning gate microscopy
- Statistics of Extreme Waves in Random Media
- Electron interferometer formed with a scanning probe tip and quantum point contact
- Transport inefficiency in branched-out mesoscopic networks: An analog of the Braess paradox
- Local Density of States in Mesoscopic Samples from Scanning Gate Microscopy
- Experimental Observation of a Fundamental Length Scale of Waves in Random Media
- Theory of scanning gate microscopy
- Imaging coherent transport in graphene (Part II): Probing weak localization
- Linear and Nonlinear Rogue Wave Statistics in the Presence of Random Currents
- Interference features in scanning gate conductance maps of quantum point contacts with disorder
- Shaping the Branched Flow of Light through Disordered Media
- Design of a scanning gate microscope in a cryogen-free dilution refrigerator
- Coherent Jetting behind a gate-defined Channel in Bilayer Graphene
- Spatially probed electron-electron scattering in a two-dimensional electron gas
- The Impact of Small-Angle Scattering on Ballistic Transport in Quantum Dots
- How branching can change the conductance of ballistic semiconductor devices
- Stability of Branched Flow from a Quantum Point Contact
- Interference of electrons in backscattering through a quantum point contact
- Imaging Andreev Reflection in Graphene
- Thermoelectric efficiency in momentum-conserving systems
- Simulations of imaging of the local density of states by charged probe technique for resonant cavities
- Partial local density of states from scanning gate microscopy
- Electron phase shift at the zero-bias anomaly of quantum point contacts
- Imaging the lateral shift of a quantum-point contact using scanning-gate microscopy
- Effects of scarring on quantum chaos in disordered quantum wells
- Scanning-gate-induced effects and spatial mapping of a cavity
- Signatures of spin-orbit coupling in scanning gate conductance images of electron flow from quantum point contacts
- How to measure the spatial correlations in disordered Berezinski-Kosterlitz-Thouless transition ?
- Scanning Gate Microscopy of a Nanostructure where Electrons Interact
- Energy Stability of Branching in the Scanning Gate Response of Two-Dimensional Electron Gases with Smooth Disorder
- Emergence and dynamical properties of stochastic branching in the electronic flows of disordered Dirac solids
- Thermal Enhancement of Interference Effects in Quantum Point Contacts
- Imaging Electron Motion in Graphene
- Is it the boundaries or disorder that dominates electron transport in semiconductor `billiards'?
- Scanning Tunneling Potentiometry, Charge Transport and Landauer's Resistivity Dipole from the Quantum to the Classical Transport Regime
- Spatial Current Patterns, Dephasing and Current Imaging in Graphene Nanoribbons
- Scanning Gate Imaging of quantum point contacts and the origin of the 0.7 Anomaly
- Imaging of double slit interference by scanning gate microscopy
- Formation of quantum dots in the potential fluctuations of InGaAs heterostructures probed by scanning gate microscopy
- Atomic Resolution Imaging of Currents in Nanoscopic Quantum Networks via Scanning Tunneling Microscopy
- Spatial mapping of disordered 2D materials: the conductance Sudoku
- Using light and heat to controllably switch and reset disorder configuration in nanoscale devices
- Numerical study of resonant spin relaxation in quasi-1D channels
- Wave function description of conductance mapping for quantum Hall electron interferometer
- Mode specific backscattering in a quantum point contact
- Electron backscattering in a cavity: ballistic and coherent effects
- Scanning gate microscopy of nonretracing electron-hole trajectories in a normal-superconductor junction
- Local imaging of high mobility two-dimensional electron systems with virtual scanning tunneling microscopy
- Theory of ballistic quantum transport in presence of localized defects
- Conductance microscopy of quantum dots weakly or strongly coupled to the conducting channel
- Local signatures of electron-electron scattering in an electronic cavity
- Electron paths and double-slit interference in the scanning gate microscopy
- Imaging signatures of the local density of states in an electronic cavity
- Supercurrent modulation in InSb nanoflag-based Josephson junctions by scanning gate microscopy
- Local Interlayer Tunneling Between Two-Dimensional Electron Systems in the Ballistic Regime
- Enlarged magnetic focusing radius of photoinduced ballistic currents
- Imaging disorder-induced scattering centers in quantum Hall incompressible strip
- Scanning gate microscopy probing of anisotropic electron flow in a two dimensional electron gas at the (110) interface: A theoretical investigation