Leland Stanford Junior University

Riken Corporation

Yongtao Cui

Zhixun Shen

Yue Ma

Yoshinori Tokura

Robert B Laughlin

Kentaro Ueda

Jun Fujioka

Control of electrical conductivity is provided via electrically conductive magnetic domain walls between magnetic domains. The magnetic domains are identical except for their magnetic configuration. Altering a configuration of the magnetic domains (e.g., by thermal treatment, application of a magnetic field, etc.) can alter the electrical resistance of a device. Such devices can be used as non-volatile information storage devices or as sensors.

Metallic-magnetic-domain-wall-based nonvolatile tunable resistor for memory and sensor applications

A microwave impedance microscope including a tuning fork having a high-aspect ratio etched metal tip electrode extending transversely to one tine of the fork and having a high aspect ratio to thereby reduce parasitic capacitance. The metal tip may be electrochemically etched from a wire, then bonded to the tine. The fork is slightly inclined from the surface of the sample and the tip electrode projects transversely to the fork. A microwave signal is impressed on the tip. Microwave circuitry receives microwave signals reflected from the sample back into the tip and demodulates the reflected signal according to the impressed signal. Further circuitry further demodulates the reflected signal according to the lower-frequency signal causing the fork to oscillate at its mechanically resonant frequency. A multi-wavelength matching circuit interposed between the microwave circuitry and the probe includes a coaxial cable of length half a fundamental microwave wavelength.

Microwave impedance microscopy using a tuning fork

Growing community of inventors

Palo Alto, CA, United States of America

Yongtao Cui