Patents by Inventor Ravindranath Viswan

Ravindranath Viswan 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: 8110255
    Abstract: The present invention discloses a method for preparation of a hybrid comprising magnetite nanoparticles and carbon nitride nanotubes, comprising: preparing carbon nitride nanotubes by plasma chemical vapor deposition (CVD); dissolving the prepared carbon nitride nanotubes in triethyleneglycol to form solution and adding Fe (acetylacetonate)3 to the solution to obtain a mixture; and heating and cooling the mixture to form a hybrid comprising magnetite nanoparticles and carbon nitride nanotubes, in which the carbon nitride nanotubes are doped with magnetite nanoparticles.
    Type: Grant
    Filed: April 21, 2010
    Date of Patent: February 7, 2012
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Jeung-Ku Kang, Jung-Woo Lee, Ravindranath Viswan, Yoon-Jung Choi, Yeob Lee, Se-Yun Kim
  • Publication number: 20100310789
    Abstract: The present invention discloses a method for preparation of a hybrid comprising magnetite nanoparticles and carbon nitride nanotubes, comprising: preparing carbon nitride nanotubes by plasma chemical vapor deposition (CVD); dissolving the prepared carbon nitride nanotubes in triethyleneglycol to form solution and adding Fe (acetylacetonate)3 to the solution to obtain a mixture; and heating and cooling the mixture to form a hybrid comprising magnetite nanoparticles and carbon nitride nanotubes, in which the carbon nitride nanotubes are doped with magnetite nanoparticles.
    Type: Application
    Filed: April 21, 2010
    Publication date: December 9, 2010
    Applicant: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Jeung-Ku Kang, Jung-Woo Lee, Ravindranath Viswan, Yoon-Jeong Choi, Yeob Lee, Se-Yun Kim
  • Patent number: 7283386
    Abstract: A voltage-controlled magnetization reversal writing type Magnetic Random Access Memory (MRAM) device. The MRAM device includes electrically conductive base electrodes, a piezoelectric layer, an insulation layer, a free ferromagnetic layer, a nonmagnetic layer, a pinned ferromagnetic layer, an antiferromagnetic layer and two electrically conductive reading lines. The electrically conductive base electrodes are provided with two writing lines having positive and negative electrodes. The left and right surfaces of piezoelectric layer are disposed to abut the writing lines of the electrically conductive base electrodes, respectively. The insulation layer is disposed beneath the piezoelectric layer and is formed to separate the positive and negative electrodes. The free ferromagnetic layer is disposed on the insulation layer. The nonmagnetic layer is disposed on the free ferromagnetic layer. The pinned ferromagnetic layer is disposed on the nonmagnetic layer.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: October 16, 2007
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sung-Chul Shin, Jong-Ryul Jeong, Ravindranath Viswan
  • Publication number: 20060133137
    Abstract: A voltage-controlled magnetization reversal writing type Magnetic Random Access Memory (MRAM) device. The MRAM device includes electrically conductive base electrodes, a piezoelectric layer, an insulation layer, a free ferromagnetic layer, a nonmagnetic layer, a pinned ferromagnetic layer, an antiferromagnetic layer and two electrically conductive reading lines. The electrically conductive base electrodes are provided with two writing lines having positive and negative electrodes. The left and right surfaces of piezoelectric layer are disposed to abut the writing lines of the electrically conductive base electrodes, respectively. The insulation layer is disposed beneath the piezoelectric layer and is formed to separate the positive and negative electrodes. The free ferromagnetic layer is disposed on the insulation layer. The nonmagnetic layer is disposed on the free ferromagnetic layer. The pinned ferromagnetic layer is disposed on the nonmagnetic layer.
    Type: Application
    Filed: December 15, 2005
    Publication date: June 22, 2006
    Inventors: Sung-Chul Shin, Jong-Ryul Jeong, Ravindranath Viswan