Synopsis: No more orders, please!

An optical fiber facilitates the transfer of energy from one laser beam to another in a nonlinear process that suppresses higher-order scattering.
Synopsis figure
Credit: M. S. Kang, Phys. Rev. Lett. (2010)

Confining light to tiny regions in space enhances its interaction with matter, leading to a host of phenomena, from surface-enhanced Raman scattering on metal surfaces to nonlinear effects in optical fibers.

Writing in Physical Review Letters, Myeong Soo Kang, Andre Brenn, and Philip Russell from the Max-Planck-Institute for the Science of Light in Erlangen, Germany, demonstrate how to harness the effects of confinement to generate a nonlinear optoacoustic effect in nanostructured photonic crystal fibers. They launch two orthogonally polarized laser beams through a birefringent fiber, in a setup that allows them to tune the frequency difference between the two beams. When this frequency offset is at a resonance, the laser pair excites a tightly confined acoustic mode in the fiber core, causing the fiber to vibrate. The acoustic mode borrows its energy from the higher frequency beam, which acts as a pump signal, and eventually transfers it to the lower frequency (Stokes) beam. This transfer of energy is similar to what happens in Raman scattering, but is designed so that no higher or lower frequency modes are excited as the optical power is increased. The result is a highly selective power transfer from the pump to the Stokes signal that occurs at a unique frequency and can be 97% efficient, in some cases.

This effect, which the authors call forward stimulated interpolarization scattering, or SIPS, may find applications in optical amplifiers, signal processing, and optical sensing. – Manolis Antonoyiannakis


Announcements

More Announcements »

Subject Areas

Optics

Previous Synopsis

Strongly Correlated Materials

A more perfect Dirac cone

Read More »

Next Synopsis

Astrophysics

Cosmic backtracking

Read More »

Related Articles

Synopsis: Position Detector Approaches the Heisenberg Limit
Quantum Physics

Synopsis: Position Detector Approaches the Heisenberg Limit

The light field from a microcavity can be used to measure the displacement of a thin bar with an uncertainty that is close to the Heisenberg limit. Read More »

Viewpoint: Next Generation Clock Networks
Atomic and Molecular Physics

Viewpoint: Next Generation Clock Networks

Free-space laser links have been used to synchronize optical clocks with an unprecedented uncertainty of femtoseconds. Read More »

Focus: How to Make an Intense Gamma-Ray Beam
Optics

Focus: How to Make an Intense Gamma-Ray Beam

Computer simulations show that blasting plastic with strong laser pulses could produce gamma rays with unprecedented intensity, good for fundamental physics experiments and possibly cancer treatments. Read More »

More Articles