Patents by Inventor Venkatesh Chembrolu
Venkatesh Chembrolu 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: 11657835Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes at least one electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: GrantFiled: April 14, 2022Date of Patent: May 23, 2023Assignee: Western Digital Technologies, Inc.Inventors: Zhigang Bai, Youfeng Zheng, Venkatesh Chembrolu, Supradeep Narayana, Yaguang Wei, Suping Song, Terence T. Lam, Kuok San Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Patent number: 11615806Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes first and second electrically conductive, non-magnetic material layers. The spin torque oscillator stack is coupled to the first electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: GrantFiled: March 17, 2022Date of Patent: March 28, 2023Assignee: Western Digital Technologies, Inc.Inventors: Zhigang Bai, Youfeng Zheng, Venkatesh Chembrolu, Supradeep Narayana, Yaguang Wei, Suping Song, Terence T. Lam, Kuok San Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Patent number: 11557314Abstract: Embodiments of the present disclosure generally relate to magnetic recording systems, and more particularly to a magnetic recording system with a current-assisted write head. The write head comprises a main pole, a trailing shield disposed above the main pole, a trailing gap disposed between the main pole and the trailing shield, a side shield surrounding three sides of the main pole, the side shield being in contact with and disposed below the trailing shield and the trailing gap, and a side gap disposed between the side shield and each of the three sides of the main pole. The side gap comprises a non-magnetic electrically-conducting material to dissipate heat away from the main pole, lowering the resistance and temperature rise due to heating. The trailing gap may further comprise a non-magnetic electrically-conducting material. The write head may have a two terminal or three terminal connection configuration.Type: GrantFiled: June 26, 2019Date of Patent: January 17, 2023Assignee: Western Digital Technologies, Inc.Inventors: Muhammad Asif Bashir, Zhigang Bai, Yaguang Wei, Terence Lam, Youfeng Zheng, Changqing Shi, Michael Kuok San Ho, Xinjiang Shen, Suping Song, Lijie Guan, Venkatesh Chembrolu
-
Patent number: 11437060Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole, a trailing shield, and a MAMR stack including at least one magnetic layer. The magnetic layer has a surface facing the main pole, and the surface has a first side at a media facing surface (MFS) and a second side opposite the first side. The length of the second side is substantially less than the length of the first side. By reducing the length of the second side, the area to be switched at a location recessed from the MFS is reduced as a current flowing from the main pole to the trailing shield or from the trailing shield to the main pole. With the reduced area of the magnetic layer, the overall switch time of the magnetic layer is decreased.Type: GrantFiled: November 30, 2020Date of Patent: September 6, 2022Assignee: Western Digital Technologies, Inc.Inventors: Venkatesh Chembrolu, Muhammad Asif Bashir, Petrus Antonius Van Der Heijden, Terence Lam, Yaguang Wei
-
Patent number: 11417356Abstract: The present disclosure generally relates to a magnetic media drive employing a magnetic recording head. The magnetic recording head comprises a main pole, a hot seed layer, and a write assist stack disposed between the main pole and the hot seed layer. In one embodiment, the write assist stack comprises a seed layer, a spin torque layer, and a notch layer. One or more of the seed layer and the notch layer have a first cross-track width and the spin torque layer has a second cross-track width less than the first cross track width. In another embodiment, the write assist stack comprises a seed layer, a spin polarization layer, and a notch layer. One or more of the seed layer and the notch layer have a first cross-track width and the spin polarization layer has a second cross-track width less than the first cross track width.Type: GrantFiled: June 30, 2020Date of Patent: August 16, 2022Assignee: Western Digital Technologies, Inc.Inventors: Muhammad Asif Bashir, Alexander Goncharov, Petrus Antonius Van Der Hemden, Aron Pentek, Yi Zhang, Venkatesh Chembrolu
-
Publication number: 20220238135Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes at least one electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: ApplicationFiled: April 14, 2022Publication date: July 28, 2022Applicant: Western Digital Technologies, Inc.Inventors: Zhigang BAI, Youfeng ZHENG, Venkatesh CHEMBROLU, Supradeep NARAYANA, Yaguang WEI, Suping SONG, Terence T. LAM, Kuok San HO, Changqing SHI, Lijie GUAN, Jian-Gang ZHU
-
Publication number: 20220208220Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes at least one electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: ApplicationFiled: March 17, 2022Publication date: June 30, 2022Inventors: Zhigang BAI, Youfeng ZHENG, Venkatesh CHEMBROLU, Supradeep NARAYANA, Yaguang WEI, Suping SONG, Terence T. LAM, Kuok San HO, Changqing SHI, Lijie GUAN, Jian-Gang ZHU
-
Patent number: 11373675Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes at least one electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: GrantFiled: January 4, 2021Date of Patent: June 28, 2022Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.Inventors: Zhigang Bai, Anna Zheng, Venkatesh Chembrolu, Supradeep Narayana, Yaguang Wei, Suping Song, Terence Lam, Michael Kuok San Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Patent number: 11017801Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and a record element located in a trailing gap between the main pole and the trailing magnetic shield. The record element includes an electrically conductive, non-magnetic material portion which is not part of a spin torque oscillator stack. The main pole and the trailing magnetic shield are electrically shorted by the record element across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the record element.Type: GrantFiled: January 18, 2019Date of Patent: May 25, 2021Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.Inventors: Venkatesh Chembrolu, Zhigang Bai, Yaguang Wei, Anna Zheng, Supradeep Narayana, Suping Song, Terence Lam, Michael Kuok San Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Patent number: 11017802Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and a record element located in a trailing gap between the main pole and the trailing magnetic shield. The record element includes an electrically conductive, non-magnetic material portion which is not part of a spin torque oscillator stack. The main pole and the trailing magnetic shield are electrically shorted by the record element across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the record element.Type: GrantFiled: August 20, 2020Date of Patent: May 25, 2021Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.Inventors: Venkatesh Chembrolu, Zhigang Bai, Yaguang Wei, Anna Zheng, Supradeep Narayana, Suping Song, Terence Lam, Michael Kouk San Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Publication number: 20210125631Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes at least one electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: ApplicationFiled: January 4, 2021Publication date: April 29, 2021Inventors: Zhigang BAI, Anna ZHENG, Venkatesh CHEMBROLU, Supradeep NARAYANA, Yaguang WEI, Suping SONG, Terence LAM, Michael Kuok San HO, Changqing SHI, Lijie GUAN, Jian-Gang ZHU
-
Patent number: 10957348Abstract: A magnetic recording write head has an electrically-conductive structure in the write gap between the write pole and the trailing shield and electrical circuitry for directing current through the write gap. The current through the electrically-conductive structure generates a circular Ampere field which, at the disk-facing end of the write pole, is substantially parallel to the disk-facing end of the write pole. The electrically-conductive structure in the write gap may be a STO or an electrically-conductive layer that is not part of a STO. The current direction through the electrically-conductive structure in the write gap is selected so that the generated Ampere field at the write pole end is in substantially the same direction as the magnetization direction of the write head side shields, which has been discovered to result in minimization of cross-track interference.Type: GrantFiled: June 24, 2020Date of Patent: March 23, 2021Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.Inventors: Zhigang Bai, Alexander Taratorin, Anna Zheng, Venkatesh Chembrolu, Supradeep Narayana, Suping Song, Yaguang Wei, Terence Lam, Michael Kuok San Ho, Changqing Shi, Lijie Guan
-
Publication number: 20210082457Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole, a trailing shield, and a MAMR stack including at least one magnetic layer. The magnetic layer has a surface facing the main pole, and the surface has a first side at a media facing surface (MFS) and a second side opposite the first side. The length of the second side is substantially less than the length of the first side. By reducing the length of the second side, the area to be switched at a location recessed from the MFS is reduced as a current flowing from the main pole to the trailing shield or from the trailing shield to the main pole. With the reduced area of the magnetic layer, the overall switch time of the magnetic layer is decreased.Type: ApplicationFiled: November 30, 2020Publication date: March 18, 2021Inventors: Venkatesh CHEMBROLU, Muhammad ASIF BASHIR, Petrus Antonius VAN DER HEIJDEN, Terence LAM, Yaguang WEI
-
Patent number: 10943616Abstract: A current-assisted magnetic recording write head has an electrically conductive layer in the write gap between the write pole and the trailing shield. Electrical circuitry directs current between the write pole and the trailing shield, through the conductive layer in the write gap. The current through the conductive layer generates an Ampere field substantially orthogonal to the magnetization in the write pole to assist magnetization switching of the write pole. The conductive layer is wider in the cross-track direction than the trailing edge of the write pole and may extend beyond the write pole side gaps so as to be in contact with both the side shields and the trailing shield. The conductive layer may have substantially the same along-the-track thickness across its width or it may have a thicker central region at the write pole trailing edge and thinner side regions.Type: GrantFiled: September 2, 2020Date of Patent: March 9, 2021Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.Inventors: Muhammad Asif Bashir, Venkatesh Chembrolu, Alexander Goncharov, Petrus Antonius Van Der Heijden, Yingjian Chen
-
Patent number: 10896690Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes at least one electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: GrantFiled: June 5, 2018Date of Patent: January 19, 2021Assignee: SANDISK TECHNOLOGIES LLCInventors: Zhigang Bai, Anna Zheng, Venkatesh Chembrolu, Supradeep Narayana, Yaguang Wei, Suping Song, Terence Lam, Michael Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Patent number: 10891975Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield. The electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion includes at least one electrically conductive, non-magnetic material layer. The main pole and the trailing magnetic shield are electrically shorted by the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the electrically conductive portion.Type: GrantFiled: January 18, 2019Date of Patent: January 12, 2021Assignee: SanDiskTechnologies LLC.Inventors: Zhigang Bai, Anna Zheng, Venkatesh Chembrolu, Supradeep Narayana, Yaguang Wei, Suping Song, Terence Lam, Michael Kuok San Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Patent number: 10891974Abstract: A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and a record element located in a trailing gap between the main pole and the trailing magnetic shield. The record element includes an electrically conductive, non-magnetic material portion which is not part of a spin torque oscillator stack. The main pole and the trailing magnetic shield are electrically shorted by the record element across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the record element.Type: GrantFiled: June 5, 2018Date of Patent: January 12, 2021Assignee: SANDISK TECHNOLOGIES LLCInventors: Venkatesh Chembrolu, Zhigang Bai, Yaguang Wei, Anna Zheng, Supradeep Narayana, Suping Song, Terence Lam, Michael Ho, Changqing Shi, Lijie Guan, Jian-Gang Zhu
-
Publication number: 20200402532Abstract: A current-assisted magnetic recording write head has an electrically conductive layer in the write gap between the write pole and the trailing shield. Electrical circuitry directs current between the write pole and the trailing shield, through the conductive layer in the write gap. The current through the conductive layer generates an Ampere field substantially orthogonal to the magnetization in the write pole to assist magnetization switching of the write pole. The conductive layer is wider in the cross-track direction than the trailing edge of the write pole and may extend beyond the write pole side gaps so as to be in contact with both the side shields and the trailing shield. The conductive layer may have substantially the same along-the-track thickness across its width or it may have a thicker central region at the write pole trailing edge and thinner side regions.Type: ApplicationFiled: September 2, 2020Publication date: December 24, 2020Inventors: Muhammad ASIF BASHIR, Venkatesh CHEMBROLU, Alexander GONCHAROV, Petrus Antonius VAN DER HEIJDEN, Yingjian CHEN
-
Patent number: 10872626Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole, a trailing shield, and a MAMR stack including at least one magnetic layer. The magnetic layer has a surface facing the main pole, and the surface has a first side at a media facing surface (MFS) and a second side opposite the first side. The length of the second side is substantially less than the length of the first side. By reducing the length of the second side, the area to be switched at a location recessed from the MFS is reduced as a current flowing from the main pole to the trailing shield or from the trailing shield to the main pole. With the reduced area of the magnetic layer, the overall switch time of the magnetic layer is decreased.Type: GrantFiled: March 5, 2019Date of Patent: December 22, 2020Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.Inventors: Venkatesh Chembrolu, Muhammad Asif Bashir, Petrus Antonius Van Der Heijden, Terence Lam, Yaguang Wei
-
Patent number: 10861485Abstract: Embodiments of the present disclosure generally relate to data storage devices, and more specifically, to storage devices employing an energy-assisted magnetic recording write head. The write head may comprise a main pole, a trailing shield, a conducting gap disposed between the main pole and the trailing shield, and one or more current blockers. The conducting gap may be conformal with the main pole. The one or more current blockers may be configured to direct the current from the main pole to the trailing shield through the conducting gap. The one or more current blockers may be further configured to recess the conducting gap away from the media facing surface. The one or more current blockers may be configured to direct the current away from a media facing surface of the write head.Type: GrantFiled: August 17, 2020Date of Patent: December 8, 2020Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.Inventors: Muhammad Asif Bashir, Yaguang Wei, Petrus Antonius Van Der Heijden, Xinjiang Shen, Terence Lam, Zhigang Bai, Youfeng Zheng, Changqing Shi, Michael Kuok San Ho, Jian-Gang Zhu, Lijie Guan, Venkatesh Chembrolu