Magnetic recording devices and methods using a write-field-enhancement structure and bias current with offset pulses

US10957346B2 · kind B2 · utility

Assignee

• Western Digital Technologies, Inc. · US

Inventors

• Gonçalo Marcos Baião De Albuquerque · San Jose, US
• Yunfei Ding · Milpitas, US
• Alexander Goncharov · معلمی نژاد, US
• Kuok San Ho · Emerald Hills, US
• Daniele Mauri · San Jose, US
• Goran Mihajlovic · San Jose, US
• Suping Song · Fremont, US
• Petrus Antonius Van Der Heijden · San Jose, US

Key dates

• Filing date: Mar 29, 2020
• Grant date: Mar 23, 2021
• Expiry date: Mar 29, 2040

Classification

• Technology area (CPC G): Physics
• CPC primary: G11B2005/0024
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

Disclosed herein are magnetic recording devices and methods of using them. A magnetic recording device comprises a main pole extending to an air-bearing surface (ABS), a trailing shield extending to the ABS, a write-field-enhancing structure disposed between and coupled to the main pole and the trailing shield at the ABS, a write coil configured to magnetize the main pole, a write current control circuit coupled to the write coil and configured to apply a write current to the write coil, wherein the write current comprises a write pulse, and a bias current control circuit coupled to the write-field-enhancing structure and configured to apply a bias current to the write-field-enhancing structure, wherein the bias current comprises a driving pulse offset in time from the write pulse by a delay, wherein the delay substantially coincides with an expected magnetization switch-time lag of a free layer of the write-field-enhancing structure.