Related Experiment Video
Updated: Aug 9, 2026
12:20
Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers
Published on: October 6, 2013
Evidence for current-flow anomalies in the irradiated 2D electron system at small magnetic fields
R L Willett1, L N Pfeiffer, K W West
1Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, New Jersey 07974, USA.
Physical Review Letters
|August 25, 2004
Summary
This study explores 2D electron systems under dipole radiation, observing magnetoresistance oscillations and unexpected voltage generation. Findings suggest potential current instabilities and negative resistivities in these systems.
Area of Science:
- Condensed matter physics
- Materials science
Background:
- Two-dimensional electron systems (2D ES) exhibit unique quantum phenomena.
- High-frequency radiation effects on electron transport are of significant research interest.
Purpose of the Study:
- To investigate the transport properties of 2D electron systems under dipole radiation up to 20 GHz.
- To analyze magnetoresistance oscillations and radiation-induced voltage generation.
Main Methods:
- Experimental measurements of transport in 2D electron systems.
- Application of dipole radiation up to 20 GHz.
- Analysis of magnetoresistance oscillations and induced voltages.
Main Results:
- Magnetoresistance oscillations were observed, with minima extending to negative biases.
- Persistent zero resistance was not observed around sample perimeters.
- Voltages were generated between contacts without applied driving currents under radiation.
Conclusions:
- Observed phenomena may indicate current instabilities in 2D electron systems.
- Findings align with theoretical models predicting local negative resistivities under specific conditions.
More Related Videos
Related Concept Videos
01:14Diamagnetic Shielding of Nuclei: Local Diamagnetic Current
An applied magnetic field causes the electrons present in the molecule to circulate, setting up a local diamagnetic current within the molecule. The local diamagnetic current arising from circulating sigma-bonding electrons induces a magnetic field, Blocal that opposes the applied magnetic field, B0. The effective magnetic field experienced by these nuclei is given by the difference between the applied and local magnetic fields in a phenomenon called local diamagnetic shielding. Essentially,...
01:27π Electron Effects on Chemical Shift: Overview
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0, resulting in...
01:28Magnetic Fields
A moving charge or a current creates a magnetic field in the surrounding space, in addition to its electric field. The magnetic field exerts a force on any other moving charge or current that is present in the field. Like an electric field, the magnetic field is also a vector field. At any position, the direction of the magnetic field is defined as the direction in which the north pole of a compass needle points.
A magnetic field is defined by the force that a charged particle experiences...
A magnetic field is defined by the force that a charged particle experiences...
01:13Magnetic Force Between Two Parallel Currents
Two long, straight, and parallel current-carrying conductors exert a force of equal magnitude on one another. The direction of the force depends on the current direction in the conductors.
The force exerted by the magnetic field due to the first conductor over a finite length of the second conductor is given as the product of the current in the second conductor and the vector product of the length vector along the current element and the field due to the first conductor. According to the...
The force exerted by the magnetic field due to the first conductor over a finite length of the second conductor is given as the product of the current in the second conductor and the vector product of the length vector along the current element and the field due to the first conductor. According to the...
01:16Magnetic Field Of A Current Loop
Consider a circular loop with a radius a, that carries a current I. The magnetic field due to the current at an arbitrary point P along the axis of the loop can be calculated using the Biot-Savart law.
01:25Magnetic Field due to Moving Charges
A stationary charge creates and interacts with the electric field, while a moving charge creates a magnetic field.
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...