• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer

Electrical Engineering News and Products

Electronics Engineering Resources, Articles, Forums, Tear Down Videos and Technical Electronics How-To's

  • Products / Components
    • Analog ICs
    • Connectors
    • Microcontrollers
    • Power Electronics
    • Sensors
    • Test and Measurement
    • Wire / Cable
  • Applications
    • Automotive/Transportation
    • Industrial
    • IoT
    • Medical
    • Telecommunications
    • Wearables
    • Wireless
  • Resources
    • DesignFast
    • Digital Issues
    • Engineering Week
    • Oscilloscope Product Finder
    • Podcasts
    • Webinars / Digital Events
    • White Papers
    • Women in Engineering
  • Videos
    • Teschler’s Teardown Videos
    • EE Videos and Interviews
  • Learning Center
    • EE Classrooms
    • Design Guides
      • WiFi & the IOT Design Guide
      • Microcontrollers Design Guide
      • State of the Art Inductors Design Guide
    • FAQs
    • Ebooks / Tech Tips
  • EE Forums
    • EDABoard.com
    • Electro-Tech-Online.com
  • 5G

Perfecting the Control of Light Waves

January 13, 2014 By TUM

Tim Paasch-Colberg with the Femtosecond-Laser at the Laboratory for Attosecond Physics. Credit: Thorsten Naeser / MPQA team at the Laboratory for Attosecond Physics (LAP) in Garching (Germany) has constructed a detector, which provides a detailed picture of the waveforms of femtosecond laser pulses (1 fs = 10-15 seconds). Knowledge of the exact waveform of these pulses enables researchers to reproducibly generate light flashes that are a thousand times shorter – lasting only for attoseconds – and can be used to study ultrafast processes at the molecular and atomic levels.

Modern mode-locked lasers are capable of producing extremely short light flashes that last for only a few femtoseconds. In one femtosecond light, which rushes from the Earth to the Moon in just one second, advances only three ten-thousandths of a millimeter. Such short pulses consist of only one or two oscillations of the electromagnetic field, which are preceded and followed by waves of lower amplitude that are rapidly attenuated. To be utilized in an optimal manner to probe ultrashort processes that occur at the level of molecules and atoms it is important to know the precise form of the high-amplitude oscillations.

A team at the Laboratory for Attosecond Physics at the Max Planck Institute for Quantum Optics (MPQ) including scientists from Technische Universitaet Muenchen (TUM), Ludwig Maximilians-Universitaet Muenchen (LMU) and further co-operation partners has now developed a glass-based detector that allows to accurately determine the form of the light waves that make up an individual femtosecond pulse.

In the course of experiments performed over the past several years, physicists in the group led by Professor Ferenc Krausz (MPQ/LMU) and Professor Reinhard Kienberger (TUM) have learned that, when pulsed high-intensity laser light impinges on glass, it induces measurable amounts of electric current in the material. Krausz and his colleagues have now found that the direction of flow of the current generated by an incident femtosecond pulse is sensitively dependent on the exact form of its wave packet.

In order to calibrate the new glass detector, the researchers coupled their system with a conventional instrument used to measure waveforms of light. Since the energy associated with the laser pulse is sufficient to liberate bound electrons from atoms of a noble gas such as xenon, the “classical” detector measures the currents caused by the motions of these free electrons. But there is a catch – the measurements must be done in a high vacuum.

By comparing the currents induced in the new solid-state detector with the data obtained using the conventional apparatus, the team was able to characterize the performance of their new glass-based set-up, so that it can now be used as a reliable phase detector for few-cycle femtosecond laser pulses. The new instrument enormously simplifies measurements in the domain of ultrafast physical processes, because one can dispense with the use of cumbersome vacuum chambers. Moreover, in its practical application the technique is much more straightforward than the methods available for the mapping of waveforms hitherto.

If the precise waveform of the femtosecond laser pulse is known, it becomes possible to reproducibly generate stable trains of ultrashort attosecond light flashes, each one a thousand times shorter than the pulse used to induce them. The composition of the attosecond flashes is in turn highly dependent on the exact shape of the femtosecond pulses. Attosecond flashes can be used to “photograph” the motions of electrons in atoms or molecules. In order to obtain high-resolution images, the length of the flashes must be tuned to take account of the material one wants to investigate.

Highly sensitive and reliable measurements of physical processes at the level of the microcosmos with the aid of single attosecond light flashes of known shape should become easier to perform because, thanks to the new glass-based phase detector, the source of the energy to drive them – the waveform of the laser pulses – can now be controlled much more easily than before.

The research was funded by the European Research Council (ERC), the Marie Curie International Incoming Fellowship Program of the European Union, the German Research Foundation via the Cluster of Excellence Munich-Centre for Advanced Photonics (MAP), the Swiss National Science Foundation and the Alexander von Humboldt Foundation.

DesignFast Banner version: 2cc05e56

Filed Under: Power Electronic Tips

Primary Sidebar

EE Training Center Classrooms

EE Classrooms

Featured Resources

  • EE World Online Learning Center
  • CUI Devices – CUI Insights Blog
  • EE Classroom: Power Delivery
  • EE Classroom: Building Automation
  • EE Classroom: Aerospace & Defense
  • EE Classroom: Grid Infrastructure
Search Millions of Parts from Thousands of Suppliers.

Search Now!
design fast globle

R&D World Podcasts

R&D 100 Episode 7
See More >

Current Digital Issue

Our second 5G Handbook is now available

Featuring 15 articles, the 2022 5G Handbook looks at private networks, timing, connectivity, latency, mmWaves, test, and other topics.

Digital Edition Back Issues

Sponsored Content

Positioning in 5G NR – A look at the technology and related test aspects

Radar, NFC, UV Sensors, and Weather Kits are Some of the New RAKwireless Products for IoT

5G Connectors: Enabling the global 5G vision

Control EMI with I-PEX ZenShield™ Connectors

Speed-up time-to-tapeout with the Aprisa digital place-and-route system and Solido Characterization Suite

Siemens Analogue IC Design Simulation Flow

More Sponsored Content >>

RSS Current EDABoard.com discussions

  • How do you find the angle made by two isosceles triangles in a kite?
  • Thermal pad construction on pcb
  • FPGA LVDS with separate clock
  • Help understanding 915MHz transciever pcb layout
  • Ansys Electronic Desktop (HFSS) file opening failed????

RSS Current Electro-Tech-Online.com Discussions

  • Flickering (candle) LED to trigger 555
  • Identify a circuit.
  • Microcontrollable adjustable and switchable constant current source for driving LED's
  • Useful Handbook for Making Low Level Measurements
  • CRYPTOOOOO, but wait i am no terrorist

Oscilloscopes Product Finder

Footer

EE World Online

EE WORLD ONLINE NETWORK

  • 5G Technology World
  • Analog IC Tips
  • Battery Power Tips
  • Connector Tips
  • DesignFast
  • EDABoard Forums
  • Electro-Tech-Online Forums
  • Engineer's Garage
  • Microcontroller Tips
  • Power Electronic Tips
  • Sensor Tips
  • Test and Measurement Tips
  • Wire & Cable Tips

EE WORLD ONLINE

  • Subscribe to our newsletter
  • Lee's teardown videos
  • Advertise with us
  • Contact us
  • About Us
Follow us on TwitterAdd us on FacebookConnect with us on LinkedIn Follow us on YouTube Add us on Instagram

Copyright © 2022 · WTWH Media LLC and its licensors. All rights reserved.
The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media.

Privacy Policy