Patent ID: 8681586
Filing Date: 2014-03-25
Classification: G01D,G01H,G01K,G01V

Abstract:
1. A gradient-sensing transducer comprising: a transducer material passively responsive to a gradient of a property of a medium in which a portion of the transducer is disposed; wherein the transducer material has an energy gap in its charge carrier energy states which energy gap is sensitive to the property, and a gradient in the property creates a corresponding gradient in the energy gap, which in turn creates a gradient in concentration of free charge carriers including electrons and holes, resulting in a diffusion flow of the free charge carriers from regions of higher concentrations to regions of lower concentrations, whereby a net electric diffusion current results due to a difference in mobilities of free charge carriers of opposite electrical charge; a pair of electrodes coupled to the transducer material; no applied or external magnetic field source having a vector field component perpendicular to a line connecting the pair of electrodes; and a measuring device electrically coupled to the pair of electrodes, wherein the measuring device is adapted to produce an output indicative of the gradient based on diffusion current density, or voltage associated with the diffusion current density, between the pair of electrodes in the transducer material.