Writing data with lasers overcomes speed limits

11 July 2014
By Edd Gent
Mobile version
Share |
An artist's impression of a laser pulse changing a magnetic bit

An artist's impression of a laser pulse changing a magnetic bit

A new ultra-fast method of writing information to hard drives using lasers could help overcome looming limits to write speed.

Hard drive stores bits in the form of tiny magnetic domains, with the directions of the magnetic north and south poles of these domains – referred to as the magnetisation – determining whether the domain represents a binary 0 or 1.

Data is stored by changing the direction of the magnetisation of the associated bits, which is currently done using a write head to create a local magnetic field to make a bit change direction.

The stronger the field, the faster the switch takes place, but this is subject to a physical limit that has now almost been reached by current information storage technology.

"The number of bits has been growing rapidly for many years, but the write speed has hardly increased. There's a need for a new data storage technology", said Eindhoven University of Technology researcher Sjors Schellekens, the lead author of a paper in Nature Communications that presents an alternative technology.

Led by Professor Bert Koopmans, the team used ultra-fast laser pulses to generate a flow of electrons in a material which all have the same spin – a quantum-mechanical property that acts like a kind of internal compass in the electron. The resulting 'spin current' is used to change the magnetic properties of the material but at a much faster rate than current technology.

Two layers with opposite magnetisation are separated by a neutral layer. When a laser pulse strikes electrons in the upper layer it causes them to move through the material, in the direction of the second layer.

The spin of these electrons exerts a force on the spin of the electrons in the lower layer to make them rotate in the same direction, altering their magnetisation.

"The change in the magnetisation is of the order of 100 femtoseconds, which is a factor 1,000 faster than what is possible with today's technology", said Schellekens. "There was discussion among physicists about whether the generated spin current is actually able to cause the change in magnetisation. We now definitely show that this is really the case."

The method is a step towards future optical computer chips, which TU Eindhoven is currently working on – in December the university received a Dutch government grant of almost €20m to integrate photonics in computer systems.

"Our technology allows optical data to be stored in the form of magnetic bits. That offers unprecedented opportunities if you want to use light as information carrier", said Schellekens.

Latest Issue

E&T cover image 1606

"Where would Frankenstein and his creative mind fit into today's workplace? Should we fear technological developments or embrace them?"

E&T jobs

  • Nuclear Facilities Governance Manager

    BAE Systems
    • England, Cumbria, Barrow-In-Furness
    • Negotiable

    Nuclear Facilities Governance Manager Would you like to be accountable for all the Nuclear Governance for both existing day to day facilities on the Barrow Site in addition to the Proposed Facilities development which is part of the multi-million pound si

    • Recruiter: BAE Systems

    Apply for this job

  • Maritime Engineering Opportunities

    Defence Equipment & Support (DE&S)
    • Bristol
    • £30,424 - £35,285

    You will be working alongside a team of people who are immensely proud of what they do in providing the best possible service to our Armed Forces

    • Recruiter: Defence Equipment & Support (DE&S)

    Apply for this job

  • Engineering Manager

    BAE Systems
    • Hampshire, England, Portsmouth
    • Competitive package

    Would you like to play a vital role in managing and implementing the correct governance in order to enable BAE Systems to provide assurance and integrity of supply chain data? We currently have a vacancy for an Engineering Manager - Product Integrity

    • Recruiter: BAE Systems

    Apply for this job

  • Consultant Engineer - Test

    BAE Systems
    • Farnborough, Hampshire, England
    • Negotiable

    Consultant Engineer - Test Would you like to be a lead within an exciting team working on one of the UK's largest defence projects? We currently have a vacancy for a Consultant Engineer - Test at our site in Ash Vale. As a Consultant Engineer - Test, you

    • Recruiter: BAE Systems

    Apply for this job

  • Structural Designer

    BAE Systems
    • England, Barrow-In-Furness, Cumbria
    • Negotiable

    Structural Designer BAE Systems is looking to recruit multiple Structural Designers to join our Maritime Submarines unit to be based in our site in Barrow-in-Furness, as the Trident Replacement Programme progresses towards the start of the build stage in

    • Recruiter: BAE Systems

    Apply for this job

  • Mechanical Design Engineer

    BAE Systems
    • England, Hampshire, Portsmouth
    • Negotiable

    Mechanical Design Engineer Would you like to work in an interesting and challenging role with the chance to gain exposure to a number of maritime projects? We currently have a vacancy for a Mechanical Design Engineer at our site in Portsmouth. As a Design

    • Recruiter: BAE Systems

    Apply for this job

  • Operations Manager

    BAE Systems
    • England, Barrow-In-Furness, Cumbria
    • Negotiable

    Operations Manager We currently have an opportunity for an Operations Manager to join our Maritime - Submarines business area at our Barrow-In-Furness site. As the Operations Manager you will work within a Construction or Manufacturing Facility and be res

    • Recruiter: BAE Systems

    Apply for this job

  • Principal Chemist

    BAE Systems
    • Barrow-In-Furness, Cumbria, England
    • Negotiable

    Principal Chemist Would you like to play a key role in the safety and assurance of submarines for the Royal Navy? We currently have a vacancy for a Principal Chemist at our site in Barrow-in-Furness. As a Principal Chemist, you will be carrying out a rang

    • Recruiter: BAE Systems

    Apply for this job

  • Software Engineer

    BAE Systems
    • England, Hampshire, Portsmouth
    • Competitive package

    As a Software Engineer, you will be investigating how technology and data can be used to optimise the services we provide to our clients, including the Royal Navy, and will include unique pieces of equipment at the forefront of innovation.

    • Recruiter: BAE Systems

    Apply for this job

  • Principal Control Systems Engineer

    BAE Systems
    • England, Cumbria, Barrow-In-Furness
    • Competitive package

    As a Principal Engineer you will be responsible for the design and integration of control systems at a safety integrity level (SIL) 3. This will include requirements management, system design, and integration into the wider platform.

    • Recruiter: BAE Systems

    Apply for this job

More jobs ▶

Subscribe

Choose the way you would like to access the latest news and developments in your field.

Subscribe to E&T