US 6,403,999 B1 · Detection of polarized spin transport in semiconductors

Abstract

Method and system for estimating a concentration of free electrons with a selected spin polarization in a semiconductor material. A static magnetic field and an electromagnetic field are impressed on the semiconductor, and free electrons are injected (through diffusion or tunneling) into the semiconductor material from a ferromagnetic material. Motion of the injected, spin-polarized electrons, within the semiconductor gives rise to a Hall voltage across the semiconductor. This voltage is measured at one or more spaced apart locations and analyzed to detect presence of, and estimate a concentration of, free electrons with a selected spin at at least one location within the semiconductor. Effects of an imposed stress, temperature, illumination or electromagnetic field on the semiconductor can be determined.

Claims24

Dependent claims

A method for estimating concentration of free electrons with a selected spin polarization in a semiconductor material, the method comprising:

positioning a ferromagnetic material adjacent to a semiconductor material at an interface;
impressing a static magnetic field with a selected field strength on the semiconductor material in a first selected direction;
impressing a selected electromagnetic field, in a direction transverse to the first direction, on the semiconductor;
injecting at least one spin-polarized free electron from the ferromagnetic material into the semiconductor, and allowing the at least one electron to move under the influence of the magnetic field and the electromagnetic field;
measuring a Hall voltage in a second selected direction across the semiconductor at at least two selected spaced apart locations in a direction transverse to the second selected direction;
and
analyzing the Hall voltage measurements to estimate a concentration of free electrons with a selected spin polarization within the semiconductor at at least one of the at least two selected locations.

4 more elements

Dependencies are inferred from the claim text.

Detection of polarized spin transport in semiconductors

Life of this patent

Detection of polarized spin transport in semiconductors

Life of this patent

Abstract

Claims24