Western Digital (fremont), Inc.

Future Wei Technologies, Inc.

Zhong Shi

Hongxing Yuan

Shing Lee

Michael V Morelli

Zhongyan Wang

Jinshan Li

Matthew R Gibbons

Yunfei Li

Lei Wang

Ut Tran

Ge Yi

Sergei L Sochava

Yufeng Hu

Wentao Yan

Ronald L Allen

Paul Y Lin

Michael L Mallary

Hai Sun

Dujiang Wan

Kuochou Tai

Jinxi Shen

Yanfeng Chen

Shawn M Tanner

Arkadi B Goulakov

Lijie Zhao

Jerome S Marcelino

Weigang Wang

Rabee M Ikkawi

Alexandre V Demtchouk

Na Shan

A technique for tuning a silicon photonics (SiP) based nested (parent/child) Mach-Zehnder modulator (MZM). The technique includes a sequence of applying dither tones on individual arms of the child MZMs, observing changes in the output of the MZM, and adjusting the MZM until reaching the null points for the child MZMs and the quad point for the parent MZM.

Optical N-level quadrature amplitude modulation (NQAM) tuned by dithering associated heaters

An apparatus includes a waveguide with first and second sections, and a junction coupling the first and second waveguide sections together. The first waveguide section has a first reflective device and the second section comprising a second reflective device arranged to generate a standing wave in the waveguide with maximum energy wave intensity at a target region of the waveguide in response to an incident energy wave being provided into at least one of the waveguide sections.

Waveguide with reflective grating for localized energy intensity

A heat-assisted magnetic recording (HAMR) transducer is coupled with a laser for providing energy and has an air-bearing surface (ABS) configured to reside in proximity to a media during use. The HAMR transducer includes a write pole, at least one coil, and an inverse tapered waveguide optically coupled with the laser. The write pole is configured to write to a region of the media. The coil(s) energize the write pole. The inverse tapered waveguide includes an entrance distal from the ABS, a bottom proximate to the ABS, a first side and a second side opposite to the first side. The first side and the second side diverging such that at least a portion of the inverse tapered waveguide between the bottom and the top is wider than the entrance.

Inverse tapered waveguide for use in a heat assisted magnetic recording head

A mode converter for use in a Heat-assisted magnetic recording (HAMR) read head to couple or bend light (e.g., from an external laser diode) into a tapered waveguide, and subsequently, to a near field transducer is provided. The mode converter may have an ultra-sharp tip, e.g., less than 200 nm to achieve a desired optical output. Manufacturing such a mode converter involves a two-pattern transform process, where overlay control (using a first edge, such as a right edge, as a reference layer relative to which positioning of a second edge, such as a left edge, is measured) allows for aligning of the right and left edges of a tip portion of the mode converter to ultimately create the ultra-sharp tip.

Method of making an ultra-sharp tip mode converter for a HAMR head

A heat-assisted magnetic recording (HAMR) transducer is coupled with a laser for providing energy and has an air-bearing surface (ABS) configured to reside in proximity to a media during use. The HAMR transducer includes a write pole, at least one coil, and a tapered waveguide optically coupled with the laser. The write pole is configured to write to a region of the media. The coil(s) energize the write pole. The tapered waveguide includes an entrance distal from the ABS, a bottom proximate to the ABS, a first side and a second side opposite to the first side. At least a portion of the first side and the second side converge in accordance with a function having at least one term having an order greater than one.

High order tapered waveguide for use in a heat assisted magnetic recording head

A heat assisted magnetic recording (HAMR) transducer on a slider and including first and second opposing surfaces, wherein the first surface is aligned to an air bearing surface (ABS) of the slider and the second surface is aligned to a surface of the slider opposite the ABS, a target waveguide having an entrance at the second surface, the target waveguide being configured to direct energy provided by a light source from the entrance toward the first surface, wherein the target waveguide expands in cross-section area with distance from the entrance to form an inverse taper waveguide, a plurality of assistant waveguides each having an entrance at the second surface, wherein the plurality of assistant waveguides are configured to direct energy to the plurality of output devices.

Assistant waveguides for evaluating main waveguide coupling efficiency and diode laser alignment tolerances for hard disk

Systems and methods for suppressing the background energy of a waveguide in an EAMR system are provided. One such system includes a near field transducer having a disk section and a pin section extending from the disk section to an air bearing surface of a slider, a waveguide having a core and a cladding, where the waveguide is configured to couple light energy to the near field transducer, where the cladding is configured to substantially surround the core, and a recess portion positioned between the core and the air bearing surface.

Systems and methods for suppressing background energy of a waveguide in an energy assisted magnetic recording system

A heat-assisted magnetic recording (HAMR) transducer is coupled with a laser for providing energy and has an air-bearing surface (ABS) configured to reside in proximity to a media during use. The HAMR transducer includes a write pole, at least one coil, a waveguide optically coupled with the laser and a grating. The write pole is configured to write to a region of the media. The coil(s) energize the write pole. The waveguide includes arms that have an optical path difference. The grating is optically coupled with the laser. The waveguide is optically coupled with the grating and receives light from the grating.

Optical grating coupling for interferometric waveguides in heat assisted magnetic recording heads

A heat assisted magnetic recording (HAMR) transducer resides on a slider, has an air-bearing surface (ABS) and has a back side. The HAMR transducer includes a target waveguide, a plurality of assistant cores and a plurality of output devices. The target waveguide has an entrance at the back side and directs energy provided by a laser from the entrance at the back side toward the ABS. The assistant cores have a plurality of assistant core entrances at the back side. The assistant cores direct energy from the assistant core entrances to the output devices. In some aspects, the assistant cores and output devices may be used in aligning the laser and the target waveguide or checking the alignment of the laser and the target waveguide.

Method and system for measuring light delivery offsets in a heat assisted magnetic recording head

Systems and methods and apparatuses for characterizing near field transducer performance at wafer level using asymmetric interference waveguides are provided. One such system includes a light source, an input grating configured to receive light from the light source, a first waveguide arm and a second waveguide arm, each configured to receive the light, a surface plasmon receptor optically coupled to the first waveguide arm and the second waveguide arm and configured to receive light from the first waveguide arm in a first direction and the second waveguide arm in a second direction opposite of the first direction, where the first and the second waveguide arms are configured to induce a preselected phase difference in light arriving at the surface plasmon receptor, and an output grating optically coupled to the surface plasmon receptor, and a light detector coupled to, and configured to detect light from, the first output grating.

Systems and methods for characterizing near field transducer performance at wafer level using asymmetric interference waveguides

A magnetic recording media is disclosed. The media comprises a substrate, a recording layer disposed over the substrate, and a metallic layer disposed between the recording layer and the substrate. The recording layer is configured to receive an electromagnetic radiation, absorb a first portion of the electromagnetic radiation, and transmit a second portion of the electromagnetic radiation. The metallic layer comprises a non-magnetic metal and configured to reflect at least some of the second portion of the electromagnetic radiation towards the recording layer.

Absorption enhanced media for energy assisted magnetic recording

A structure for measuring energy absorption by a surface plasmon receptor or NFT on a waveguide comprises a first waveguide, a first input grating for coupling light comprising a first wavelength into the first waveguide, a first output grating for coupling light out of the first waveguide, a first plurality of surface plasmon receptors in cooperation with the first waveguide to receive light energy and located between the first input grating and the first output grating. The structure may further comprise a second waveguide, a second input grating for coupling light into the second waveguide, a second output grating for coupling light out of the second waveguide, a second plurality of surface plasmon receptors between the second input grating and the second output grating and in cooperation with the second waveguide to receive light energy, wherein the second plurality may be less than or greater than the first plurality.

Structure and method to measure waveguide power absorption by surface plasmon element

An EAMR disk drive includes a media, a laser, and a slider coupled with the laser. The laser for provides energy. The slider has an air-bearing surface, a laser input side, an EAMR transducer and an antireflective coating (ARC) layer occupying a portion of the laser input side. The ARC layer is configured to reduce back reflections of the energy. The EAMR transducer includes a write pole, a waveguide optically coupled with the laser and at least one coil. The waveguide has a waveguide input. A portion of the ARC layer resides between the laser and the waveguide input. A method aligns the laser to the ARC layer, and then aligns the laser to the waveguide input. The laser may then be coupled to the slider.

Method and system for improving laser alignment and optical transmission efficiency of an energy assisted magnetic recording head

Systems and methods for increasing media absorption efficiency using interferometric waveguides in information storage devices are described. One such system for an interferometric waveguide assembly includes a light source, a first waveguide arm and a second waveguide arm, a splitter configured to receive light from the light source and to split the light into the first waveguide arm and the second waveguide arm, and a near field transducer (NFT) configured to receive the light from the first waveguide arm and the second waveguide arm, where the first waveguide arm and the second waveguide arm converge to form a preselected angle at a junction about opposite the splitter, and where the first waveguide arm and the second waveguide arm are configured to induce a preselected phase difference in the light arriving at the NFT.

Growing community of inventors

Dublin, CA, United States of America

Zhong Shi