Ballistic electron transport beyond 100 microm IN 2D electron systems

doi:10.1016/0039-6028(90)90310-5

Surface Science

Volume 228, Issues 1–3, 1 April 1990, Pages 283-285

https://doi.org/10.1016/0039-6028(90)90310-5 Get rights and content

Abstract

We have observed ballistic electron transport beyond 100 microm in the 2D electron system of an ultra-high mobility GaAs(AlGa)As heterostructure employing a magnetic electron focusing technique through wide point contacts. The amplitude of the characteristic magneto-oscillations is found to depend exponentially on electron propagation distance with a decay length λ_a = 15 microm. λ_a differs by about a factor of 2 from the mobility mean free path of 28 microm. This may indicate the determination of a different angular average of scattering events in focusing experiments as compared to standard mobility measurements.

References (5)

H. van Houten et al.
Europhys. Lett.
(1988)
C.W.J. Beenakker et al.
Festkörperprobleme

There are more references available in the full text version of this article.

Cited by (66)

Temperature dependence of relaxation times in electron focusing and antidot structures made from In<inf>0.53</inf>Ga<inf>0.47</inf>As/InP heterojunctions
1998, Superlattices and Microstructures
The magnetoresistance of antidot lattices and the magnetic field dependence of the three-terminal resistance of transverse electron focusing (TEF) devices is studied in a 2DEG in the lattice-matched In_0.53Ga_0.47As/InP heterojunction system, as a function of temperature. Ballistic effects are observed in both types of mesoscopic devices at temperatures exceeding 100 K, and are considerably more robust than Shubnikov–de Haas (SdH) oscillations. Two effects influence the decay in the amplitude of the magnetoresistance peaks in the antidot structures, and of the focusing peaks in the TEF devices: the thermal smearing of the Fermi surface, and the increase in the electron scattering time with increasing temperature due to the increase in electron–phonon scattering. We deduce the temperature dependencies of the scattering times for the different geometries.Copright 1998 Academic Press
Ballistic transport in the upper subband of a two-dimensional electron system
1996, Physica B: Condensed Matter
We report the observation of ballistic transport of upper subband electrons in a two-dimensional electron system (2DES) confined to a square quantum well with two occupied electrical subbands. We have performed two types of experiments. In the first type, we use a specially designed transverse magnetic focusing device in which the usual reflecting barrier is replaced by a surface-gate-induced, tunable potential barrier to selectively reflect and magnetically focus the upper subband electrons. In the second type of experiment, we create a surface-gate-induced, periodic potential in a double-subband-occupied 2DES and measure the magnetoresistance along the modulation direction. Fourier analysis is used to separate the commensurability oscillations originating from ballistic electrons of different subbands.
Transverse electron focusing
1996, Physica B: Condensed Matter
Effect of a charged scanned probe microscope tip on a subsurface electron gas
1996, Superlattices and Microstructures
Using a cryogenic scanned probe microscope (SPM) one can locally modify the sheet density of a two-dimensional electron gas (2DEG), and image the ballistic flow of electrons through a point contact in the 2DEG located beneath the surface of a GaAs/AlGaAs heterostructure. We calculate the capacitively induced change in sheet density when a charged SPM tip is brought into contact with a semiconductor heterostructure containing a two-dimensional electron gas. A simple scattering model, based on a local change in sheet density, is used to analyze experimental data taken with the SPM method described above.
Experimental evidence for composite fermions
1997, Semiconductor Science and Technology
Fractional focusing peaks and collective dynamics in two-dimensional Fermi liquids
2023, arXiv

View all citing articles on Scopus

View full text

Ballistic electron transport beyond 100 microm IN 2D electron systems

Abstract

Europhys. Lett.

Festkörperprobleme