Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Flatland light

07.11.2019

Researchers create rewritable optical components for 2D light waves

In 1884, a schoolmaster and theologian named Edwin Abbott wrote a novella called Flatland, which tells the story of a world populated by sentient two-dimensional shapes. While intended as a satire of rigid Victorian social norms, Flatland has long fascinated mathematicians and physicists and served as the setting for many a thought experiment.


A 2D prism

Credit: Harvard SEAS


A 2D lens

Credit: Harvard SEAS

One such thought experiment: How can light be controlled in two dimensions?

When a wave of light is confined on a two-dimensional plane by certain materials, it becomes something known as a polariton -- a particle that blurs the distinction between light and matter. Polaritons have exciting implications for the future of optical circuits because, unlike electronic integrated circuits, integrated optics is difficult to miniaturize with commonly used materials. Polaritons allow light to be tightly confined to the nanoscale, even potentially to the thickness of a few atoms.

The challenge is, all of the ways we currently have to control light - lenses, waveguides, prisms -- are three dimensional.

"The ability to control and confine light with fully reprogrammable optical circuits is vital for future highly-integrated nanophotonic devices," said Michele Tamagnone, a postdoctoral fellow in Applied Physics at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS).

Now, Tamagnone and a team of researchers at SEAS have developed rewritable optical components for surface light waves. The research was published in Nature Communications.

In previous research, the team, led by Federico Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering, demonstrated a technique to create and control polaritons by trapping light in a flake of hexagonal boron nitride. In this study, the researchers put those flakes on the surface of a material known as GeSbTe (GST) -- the same materials used on the surface of rewritable CDs and Blu-ray discs.

"The rewritable property of GST using simple laser pulses allows for the recording, erasing and rewriting of information bits. Using that principle, we created lenses, prisms and waveguides by directly writing them into the material layer," said Xinghui Yin, a postdoctoral fellow at SEAS and co-first author of the study.

The lenses and prisms on this material are not three-dimensional objects as in our world, but rather two-dimensional shapes, as they would be in Flatland. Instead of having a semispherical lens, the polaritons on the Flatland-esc material pass through a flat semicircle of refracting material that act as a lens. Instead of traveling through a prism, they travel through a triangle and instead of optical fibers, the polaritons move through a simple line, which guides the waves along a predefined path.

Using a technique known as near-field microscopy, which allows the imaging of features much smaller than the wavelength of light, the researchers were able to see these components at work. They also demonstrated for the first time that it is possible to erase and rewrite the optical components that they created.

"This research could lead to new chips for applications such as single molecule chemical sensing, since the polaritons in our rewritable devices correspond to frequencies in the region of spectrum where molecules have their telltale absorption fingerprints," said Capasso.

###

This research was co-first-authored by Kundan Chaudhary and Christina M. Spägele and co-authored by Stefano L. Oscurato, Jiahan Li, Christoph Persch, Ruoping Li, Noah A. Rubin, Luis A. Jauregui, Kenji Watanabe, Takashi Taniguchi, Philip Kim, Matthias Wuttig, James H. Edgar, and Antonio Ambrosio.

It was supported by the National Science Foundation.

Media Contact

Leah Burrows
lburrows@seas.harvard.edu
617-496-1351

 @hseas

http://www.seas.harvard.edu/ 

Leah Burrows | EurekAlert!
Further information:
https://www.seas.harvard.edu/news/2019/11/flatland-light
http://dx.doi.org/10.1038/s41467-019-12439-4

More articles from Physics and Astronomy:

nachricht FAST detects neutral hydrogen emission from extragalactic galaxies for the first time
02.07.2020 | Chinese Academy of Sciences Headquarters

nachricht First exposed planetary core discovered
01.07.2020 | Universität Bern

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electrons in the fast lane

Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.

Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....

Im Focus: The lightest electromagnetic shielding material in the world

Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.

Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...

Im Focus: Gentle wall contact – the right scenario for a fusion power plant

Quasi-continuous power exhaust developed as a wall-friendly method on ASDEX Upgrade

A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...

Im Focus: ILA Goes Digital – Automation & Production Technology for Adaptable Aircraft Production

Live event – July 1, 2020 - 11:00 to 11:45 (CET)
"Automation in Aerospace Industry @ Fraunhofer IFAM"

The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM l Stade is presenting its forward-looking R&D portfolio for the first time at...

Im Focus: AI monitoring of laser welding processes - X-ray vision and eavesdropping ensure quality

With an X-ray experiment at the European Synchrotron ESRF in Grenoble (France), Empa researchers were able to demonstrate how well their real-time acoustic monitoring of laser weld seams works. With almost 90 percent reliability, they detected the formation of unwanted pores that impair the quality of weld seams. Thanks to a special evaluation method based on artificial intelligence (AI), the detection process is completed in just 70 milliseconds.

Laser welding is a process suitable for joining metals and thermoplastics. It has become particularly well established in highly automated production, for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International conference QuApps shows status quo of quantum technology

02.07.2020 | Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

 
Latest News

Rising water temperatures could endanger the mating of many fish species

03.07.2020 | Life Sciences

Risk of infection with COVID-19 from singing: First results of aerosol study with the Bavarian Radio Chorus

03.07.2020 | Studies and Analyses

Efficient, Economical and Aesthetic: Researchers Build Electrodes from Leaves

03.07.2020 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>