Nav: Home

World first demo of labyrinth magnetic-domain-optical Q-switched laser

July 27, 2016

The "Industry 4.0" concept, first introduced by the German government, has recently extended the scope of compact high-power laser applications to, for instance, laser manufacturing, vehicle engine development, or thruster systems for space exploration.

However, integration of a controllable Q-switch into compact solid-state lasers has been challenging because of the mechanisms of EO and AO effects. In addition, previous Q-switches needed a large-sized power supply, which prevented downscaling of the entire system.

Now, researchers at Toyohashi University of Technology, Iowa State University, and the Institute for Molecular Science have developed a magneto-optic (MO) Q-switched laser for the first time, using a 190-micron-thick magnetic garnet film with labyrinth-shaped magnetic domains. They used custom-made coil and circuits to generate the pulsed magnetic field to be applied to the magnetic garnet, and successfully generated optical output with a pulse width of tens of nanoseconds. This is the first demonstration ever of a Q-switched laser driven by magnetic domain motions, and also the first evidence of the possibility of an integrated Q-switched laser. "The device was two orders of magnitude smaller than other reported controllable Q-switches," commented Associate Professor Taira.

"The most difficult part of realizing MO Q-switching was to combine three different techniques/fields: the preparation of a magnetic material, the fabrication of a high-speed magnetic field switch, and the construction of a laser cavity," explained PhD candidate Ryohei Morimoto.

According to the first author, Assistant Professor Taichi Goto, "there are no previous reports of MO Q-switches using thin garnets. This is surely the first demonstration, and it also becomes an important first step in the development of an integrated high-power laser."

"We enjoy our collaboration and learn from each other," said Professor Mina Mani. "We further hope not only to advance research and create and pursue new challenges, but also to use science and technology to make a better world for all."

In addition, the researchers found a unique biasing technique that uses magnetism to decrease the electric power needed for Q-switching. When a ring-shaped permanent magnet was placed close to the magnetic garnet, they were able to generate the same optical pulse in the MO Q-switched laser using seven times less electric power. This result showed that this Q-switch does not need a large power supply for operation, meaning that drastic downscaling can be expected. The research team would like their future studies to be useful for laser users all around the world and to help in the establishment of new industries.
-end-
We acknowledge support from the following institutions:

- Japan Society for the Promotion of Science (JSPS) KAKENHI Nos. 26706009, 26600043, 26220902, 25820124, and 15H02240.

- Japan Science and Technology Agency (JST) - Promoting individual research to nurture the seeds of future innovation and organizing unique, innovative network (PRESTO).

Reference:

T. Goto, R. Morimoto, J. W. Pritchard, M. Mina, H. Takagi, Y. Nakamura, P. B. Lim, T. Taira, and M. Inoue, (2016)."Magneto-optical Q-switching using magnetic garnet film with micromagnetic domains," Opt. Express, 24, (16), 17635-17643. DOI: 10.1364/OE.24.017635.

Further information

Toyohashi University of Technology
1-1 Hibarigaoka, Tempaku
Toyohashi, Aichi Prefecture, 441-8580, JAPAN
Inquiries: Committee for Public Relations
E-mail: press@office.tut.ac.jp

Toyohashi University of Technology, which was founded in 1976 as a National University of Japan, is a leading research institute in the fields of mechanical engineering, advanced electronics, information sciences, life sciences, and architecture.

Website: http://www.tut.ac.jp/english/

Toyohashi University of Technology

Related Technology Articles:

Post-lithium technology
Next-generation batteries will probably see the replacement of lithium ions by more abundant and environmentally benign alkali metal or multivalent ions.
Rethinking the role of technology in the classroom
Introducing tablets and laptops to the classroom has certain educational virtues, according to Annahita Ball, an assistant professor in the University at Buffalo School of Social Work, but her research suggests that tech has its limitations as well.
The science and technology of FAST
The Five hundred-meter Aperture Spherical radio Telescope (FAST), located in a radio quiet zone, with the targets (e.g., radio pulsars and neutron stars, galactic and extragalactic 21-cm HI emission).
AI technology could help protect water supplies
Progress on new artificial intelligence (AI) technology could make monitoring at water treatment plants cheaper and easier and help safeguard public health.
Transformative technology
UC Davis neuroscientists have developed fluorescence sensors that are opening a new era for the optical recording of dopamine activity in the living brain.
Do the elderly want technology to help them take their medication?
Over 65s say they would find technology to help them take their medications helpful, but need the technology to be familiar, accessible and easy to use, according to research by Queen Mary University of London and University of Cambridge.
Technology detecting RNase activity
A KAIST research team of Professor Hyun Gyu Park at Department of Chemical and Biomolecular Engineering developed a new technology to detect the activity of RNase H, a RNA degrading enzyme.
Taking technology to the next level
Physicists from the ARC Centre of Excellence for Ultrahigh bandwidth Devices for Optical Systems (CUDOS) developed a new hybrid integrated platform, promising to be a more advanced alternative to conventional integrated circuits.
How technology use affects at-risk adolescents
More use of technology led to increases in attention, behavior and self-regulation problems over time for adolescents already at risk for mental health issues, a new study from Duke University finds.
Hold-up in ventures for technology transfer
The transfer of technology brings ideas closer to commercialization. The transformation happens in several steps, such as invention, innovation, building prototypes, production, market introduction, market expansion, after sales services.
More Technology News and Technology Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#542 Climate Doomsday
Have you heard? Climate change. We did it. And it's bad. It's going to be worse. We are already suffering the effects of it in many ways. How should we TALK about the dangers we are facing, though? Should we get people good and scared? Or give them hope? Or both? Host Bethany Brookshire talks with David Wallace-Wells and Sheril Kirschenbaum to find out. This episode is hosted by Bethany Brookshire, science writer from Science News. Related links: Why Climate Disasters Might Not Boost Public Engagement on Climate Change on The New York Times by Andrew Revkin The other kind...
Now Playing: Radiolab

An Announcement from Radiolab