Patents by Inventor Samuel D. Bader

Samuel D. Bader has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7639359
    Abstract: A biosensor utilizing bio-functionalized magnetic nanoparticles is provided. An external magnetic field is applied to a suspension of magnetic nanoparticles. A linearly polarized incident light is applied to the suspension of magnetic nanoparticles. A photocurrent from polarized light scattering by bio-functionalized magnetic nanoparticles in liquid is detected. The magneto-optic sensing technique is applied to a micro-fluidic channel for rapid and sensitive detection with a small sample amount, and subsequent magnetic separation for detoxification. This technique is used for the detection of Brownian relaxation with time sweep as well as frequency sweep. The magneto-optical sensor enables rapidly detecting changes in local dynamic properties of the magnetic nanoparticles in liquids and magnetic modulation of ferromagnetic particles in liquid provides increased signal sensitivity.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: December 29, 2009
    Assignee: UChicagoArgonne, LLC
    Inventors: Seok-Hwan Chung, Axel F. Hoffmann, Samuel D. Bader
  • Publication number: 20090033935
    Abstract: A biosensor utilizing bio-functionalized magnetic nanoparticles is provided. An external magnetic field is applied to a suspension of magnetic nanoparticles. A linearly polarized incident light is applied to the suspension of magnetic nanoparticles. A photocurrent from polarized light scattering by bio-functionalized magnetic nanoparticles in liquid is detected. The magneto-optic sensing technique is applied to a micro-fluidic channel for rapid and sensitive detection with a small sample amount, and subsequent magnetic separation for detoxification. This technique is used for the detection of Brownian relaxation with time sweep as well as frequency sweep. The magneto-optical sensor enables rapidly detecting changes in local dynamic properties of the magnetic nanoparticles in liquids and magnetic modulation of ferromagnetic particles in liquid provides increased signal sensitivity.
    Type: Application
    Filed: October 19, 2007
    Publication date: February 5, 2009
    Applicant: UChicago Argonne, LLC
    Inventors: Seok-Hwan Chung, Axel F. Hoffmann, Samuel D. Bader
  • Patent number: 6272036
    Abstract: A system for controlling the direction of magnetization of materials comprising a ferromagnetic device with first and second ferromagnetic layers. The ferromagnetic layers are disposed such that they combine to form an interlayer with exchange coupling. An insulating layer and a spacer layer are located between the first and second ferromagnetic layers. A direct bias voltage is applied to the interlayer exchange coupling, causing the direction of magnetization of the second ferromagnetic layer to change. This change of magnetization direction occurs in the absence of any applied external magnetic field.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: August 7, 2001
    Assignee: The University of Chicago
    Inventors: Chun-Yeol You, Samuel D. Bader
  • Patent number: 6249453
    Abstract: A reprogrammable logic gate comprising first and second voltage-controlled rotation transistors. Each transistor comprises three ferromagnetic layers with a spacer and insulating layer between the first and second ferromagnetic layers and an additional insulating layer between the second and third ferromagnetic layers. The third ferromagnetic layer of each transistor is connected to each other, and a constant external voltage source is applied to the second ferromagnetic layer of the first transistor. As input voltages are applied to the first ferromagnetic layer of each transistor, the relative directions of magnetization of the ferromagnetic layers and the magnitude of the external voltage determines the output voltage of the gate. By altering these parameters, the logic gate is capable of behaving as AND, OR, NAND, or NOR gates.
    Type: Grant
    Filed: April 18, 2000
    Date of Patent: June 19, 2001
    Assignee: The University of Chicago
    Inventors: Chun-Yeol You, Samuel D. Bader
  • Patent number: 5116693
    Abstract: A high density magneto-optical information storage medium utilizing the properties of an ultrathin iron film on a palladium substrate. The present invention comprises a magneto-optical medium capable of thermal and magnetic stability and capable of possessing a vertical orientation of the magnetization vector for the magnetic material. Data storage relies on the temperature dependence of the coercivity of the ultrathin film. Data retrieval derives from the Kerr effect which describes the direction of rotation of a plane of polarized light traversing the ultrathin magnetic material as a function of the orientation of the magnetization vector.
    Type: Grant
    Filed: May 22, 1990
    Date of Patent: May 26, 1992
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Chian Q. Liu, Samuel D. Bader