Leland Stanford Junior University

Riken Corporation

Zhixun Shen

Nicholas A Melosh

Jared W Schwede

Yue Ma

Yongtao Cui

Yoshinori Tokura

Robert B Laughlin

Igor Bargatin

Kentaro Ueda

Kunal Sahasrabuddhe

Daniel Riley

Jun Fujioka

Jared Schwede

The embodiments provide a thermionic emission device and a method for tuning a work function in a thermionic emission device is provided. The method includes illuminating an N type semiconductor material of a first member of a thermionic emission device, wherein a work function of the N type semiconductor material is lowered by the illuminating. The method includes collecting, on one of the first member or a second member of the thermionic emission device, electrons emitted from one of the first member or the second member.

Method for tuning work function using surface photo voltage and producing ultra-low-work-function surfaces, and devices operational therewith

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

Photon Enhanced Thermionic Emission (PETE) is exploited to provide improved efficiency for radiant energy conversion. A hot (greater than 200&#xb0; C.) semiconductor cathode is illuminated such that it emits electrons. Because the cathode is hot, significantly more electrons are emitted than would be emitted from a room temperature (or colder) cathode under the same illumination conditions. As a result of this increased electron emission, the energy conversion efficiency can be significantly increased relative to a conventional photovoltaic device. In PETE, the cathode electrons can be (and typically are) thermalized with respect to the cathode. As a result, PETE does not rely on emission of non-thermalized electrons, and is significantly easier to implement than hot-carrier emission approaches.

Photon enhanced thermionic emission

Growing community of inventors

Stanford, CA, United States of America

Zhixun Shen