Featured Research

from universities, journals, and other organizations

Nonlinear optics: Now in the terahertz range

Date:
June 13, 2012
Source:
Technical University of Denmark (DTU)
Summary:
Researchers have recently reported on the direct observation of a nonlinear-optical effect, occurring in the regime of single-cycle pulse of light at terahertz (THz) frequencies. They used a doped semiconductor as an efficient nonlinear medium, where the THz-range optical nonlinearity arises from the response of free-electron plasma to THz electric fields.

As the field strength in the incident THz pulse (the one on the left) grows, the THz pulse transmitted through the semiconductor (the one on the right) experiences a larger time delay due to self-phase modulation.
Credit: DTU

The researchers at DTU Fotonik, Max Planck Institute for Polymer Research -- MPIP (Mainz, Germany), and SLAC Linear Accelerator Laboratory (California, USA) have recently reported on the direct observation of a nonlinear-optical effect, occurring in the regime of single-cycle pulse of light at terahertz (THz) frequencies. In their paper, published in Physical Review B , they used a doped semiconductor as an efficient nonlinear medium, where the THz-range optical nonlinearity arises from the response of free-electron plasma to THz electric fields.

Related Articles


The single-cycle pulses of THz light, propagating through such a medium, experienced an effect called the self-phase modulation (SPM), which led to the nonlinear reshaping and time delay of the THz pulses. The SPM is one of the most important effects in nonlinear optics. It is used in numerous applications, ranging from supercontinuum generation for biophotonics imaging to ultra-high speed optical signal processing in telecom systems.

Single-cycle pulses, irrespective of the frequency range to which they belong, inherently have an extremely broad spectral bandwidth covering many octaves of frequencies. Unlike the single-cycle pulses at optical frequencies, the THz pulses can be easily generated and detected in the time-domain using conventional femtosecond lasers. One of the discoveries in this work was the coexistence of both positive and negative refractive index nonlinearity within the broad spectrum of a single-cycle THz pulse. This is quite a unique observation for nonlinear optics in general, which demonstrates a great potential of using THz pulses as accessible model tools for study of single-cycle nonlinear optical effects.


Story Source:

The above story is based on materials provided by Technical University of Denmark (DTU). Note: Materials may be edited for content and length.


Journal Reference:

  1. Dmitry Turchinovich, Jørn Hvam, Matthias Hoffmann. Self-phase modulation of a single-cycle terahertz pulse by nonlinear free-carrier response in a semiconductor. Physical Review B, 2012; 85 (20) DOI: 10.1103/PhysRevB.85.201304

Cite This Page:

Technical University of Denmark (DTU). "Nonlinear optics: Now in the terahertz range." ScienceDaily. ScienceDaily, 13 June 2012. <www.sciencedaily.com/releases/2012/06/120613102128.htm>.
Technical University of Denmark (DTU). (2012, June 13). Nonlinear optics: Now in the terahertz range. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2012/06/120613102128.htm
Technical University of Denmark (DTU). "Nonlinear optics: Now in the terahertz range." ScienceDaily. www.sciencedaily.com/releases/2012/06/120613102128.htm (accessed October 24, 2014).

Share This



More Matter & Energy News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

3D Printed Instruments Make Sweet Music in Sweden

3D Printed Instruments Make Sweet Music in Sweden

Reuters - Innovations Video Online (Oct. 23, 2014) — Students from Lund University's Malmo Academy of Music are believed to be the world's first band to all use 3D printed instruments. The guitar, bass guitar, keyboard and drums were built by Olaf Diegel, professor of product development, who says 3D printing allows musicians to design an instrument to their exact specifications. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Chameleon Camouflage to Give Tanks Cloaking Capabilities

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Reuters - Innovations Video Online (Oct. 22, 2014) — Inspired by the way a chameleon changes its colour to disguise itself; scientists in Poland want to replace traditional camouflage paint with thousands of electrochromic plates that will continuously change colour to blend with its surroundings. The first PL-01 concept tank prototype will be tested within a few years, with scientists predicting that a similar technology could even be woven into the fabric of a soldiers' clothing making them virtually invisible to the naked eye. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Jet Sales Lift Boeing Profit 18 Pct.

Jet Sales Lift Boeing Profit 18 Pct.

Reuters - Business Video Online (Oct. 22, 2014) — Strong jet demand has pushed Boeing to raise its profit forecast for the third time, but analysts were disappointed by its small cash flow. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Internet of Things Aims to Smarten Your Life

Internet of Things Aims to Smarten Your Life

AP (Oct. 22, 2014) — As more and more Bluetooth-enabled devices are reaching consumers, developers are busy connecting them together as part of the Internet of Things. (Oct. 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins