A pulse of light normally has many cycles of smoothly varying electric and magnetic fields. Through the use of special fibers, prisms, and optical materials, a pulse of light can be compressed down to very short temporal durations, even as short as a single cycle (only one complete wavelength of radiation).
A major reason for wanting shorter light pulses is that more data can be encoded within a signal lasting a certain interval of time. Shorter pulses would allow more data to be sent down an optical fiber, for example. Another important scientific use of very short pulses is that they can serve as a stroboscopic illumination for making movies of very short-lived phenomena, such as the movement and interactions of molecules.
Scientists at the University of Konstanz in Germany are the first to report creating a single-cycle pulse as short as 4.3 femtoseconds in the infrared region of light (which is the crucial type of light for communications applications) around 1.3 microns in wavelength. Guenther Krauss, who works with Alfred Leitenstorfer in the Department of Physics, says that another distinction of the light is that it has the highest frequency ever achieved for single-cycle pulses.
With such short light pulses, the data transmission rate for applications like the Internet might reach rates of 100 terabits per second, says Krauss. Furthermore, the femtosecond (10-15 seconds) pulses created in the current experiments might serve as the seed for making even shorter pulses in the attosecond (10-18 seconds) domain.
The work is being reported at the 2010 Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS) May 16-21 at the San Jose McEnery Convention Center in San Jose, Calif., where researchers from around the world are presenting the latest breakthroughs in electro-optics, innovative developments in laser science, and commercial applications in photonics.
Presentation: "Single-Cycle Light Pulses from a Compact Er: Fiber Laser," by Guenther Krauss et al is at 4:45 p.m. Wednesday, May 19.
Cite This Page: