RP Photonics logo
RP Photonics
Consulting Software Encyclopedia Buyer's Guide

Short address: rpp-con.com

Dr. Paschotta, the founder of RP Photonics, supports your R & D with his deep expertise. Save time and money with efficient support!

Short address: rpp-soft.com

Powerful simulation software for fiber lasers and amplifiers, resonator design, pulse propagation and multilayer coating design.

Short address: rpp-enc.com

The famous Encyclopedia of Laser Physics and Technology provides a wealth of high-quality scientific and technical information.

Short address: rpp-bg.com

In the RP Photonics Buyer's Guide, you easily find suppliers for photo­nics products. As a supp­lier, you can profit from enhanced entries!

Learn on lasers and photonics every day!
VL logo part of the

Electroabsorption Modulators

<<<  |  >>>  |  Feedback

Buyer's Guide

The ideal place to find suppliers for photonics products: high-quality information, simple and fast, respects your privacy!

3 suppliers for electroabsorption modulators are listed.

Your are not yet listed? Get your entry!

Acronym: EAM

Definition: optical modulators based on the Franz–Keldysh effect

German: Elektroabsorptionsmodulatoren

An electroabsorption modulator (or electro-absorption modulator) is a semiconductor device which can be used for controlling (modulating) the intensity of a laser beam via an electric voltage (→ optical modulators). Its principle of operation is based on the Franz–Keldysh effect [1, 2], i.e., a change in the absorption spectrum caused by an applied electric field, which changes the bandgap energy (thus the photon energy of an absorption edge) but usually does not involve the excitation of carriers by the electric field.

Most electroabsorption modulators are made in the form of a waveguide with electrodes for applying an electric field in a direction perpendicular to the modulated light beam. For achieving a high extinction ratio, one usually exploits the quantum-confined Stark effect in a quantum well structure.

Compared with electro-optic modulators, electroabsorption modulators can operate with much lower voltages (a few volts instead of hundreds of thousands of volts). They can be operated at very high speed; a modulation bandwidth of tens of gigahertz can be achieved, which makes these devices useful for optical fiber communications. A convenient feature is that an electroabsorption modulator can be integrated with a distributed feedback laser diode on a single chip to form a data transmitter in the form of a photonic integrated circuit. Compared with direct modulation of the laser diode, a higher bandwidth and reduced chirp can be obtained.


[1]L. V. Keldysh, “Behaviour of non-metallic crystals in strong electric fields”, J. Exp. Theor. Phys. (USSR) 33, 994 (1957); translation: Sov. Phys. JETP 6, 763 (1958)
[2]W. Franz, “Einfluß eines elektrischen Feldes auf eine optische Absorptionskante”, Z. Naturforsch., Teil A 13, 484 (1958)
[3]E. Lach et al., “Application of electroabsorption modulators for high-speed transmission systems”, J. Opt. Fiber Commun. Rep. 2, 140–170 (2005)
[4]J. Liu et al., “Waveguide-integrated, ultralow-energy GeSi electro-absorption modulators”, Nature Photon. 2, 433 (2008)

See also: electro-optic modulators, optical modulators

Category: photonic devices

How do you rate this article?

Your general impression: don't know poor satisfactory good excellent
Technical quality: don't know poor satisfactory good excellent
Usefulness: don't know poor satisfactory good excellent
Readability: don't know poor satisfactory good excellent

Found any errors? Suggestions for improvements? Do you know a better web page on this topic?

Spam protection: (enter the value of 5 + 8 in this field!)

If you want a response, you may leave your e-mail address in the comments field, or directly send an e-mail.

If you like our website, you may also want to get our newsletters!

cover of print encyclopedia

The Encyclopedia of Laser Physics and Technology is also available in the form of a two-volume book. Maybe you would enjoy reading it also in that form! The print version has a carefully designed layout and can be considered a must-have for any institute library, laser research group, or laser company. You may order the print version via Wiley-VCH.


Have you seen the
RP Photonics Buyer's Guide?

It lists many hundreds of suppliers for photonics products, and is just one mouse click away from the extremely popular Encyclopedia of Laser Physics and Technology:

Our Buyer's Guide is what you need:

And surely you will remember where to find this useful resource again!

Suppliers: get your free entries, and enhanced visibility with paid entries.

Beam Propagation Software

Analyze beam propagation in specialty fibers, waveguides, couplers, etc. with the new version of RP Fiber Power!

beam propagation

Stay Up to Date with Newsletters

Obtain the Photonics Spotlight and the RP Photonics Software News as a newsletter! We spread interesting information, not just advertisements.

New Fiber Optics Software!

RP Fiber Calculator software

RP Fiber Calculator – a convenient tool for calculations on optical fibers -- offered for free within the 10-year anniversary of RP Photonics, and also as a PRO version with even more powerful features!

Read a random article every day in order to steadily learn about photonics!

RP Photonics Buyer's Guide

Do you know a better place to find suppliers for photonics items? Search by product or by supplier.

Suppliers, show your products with free or enhanced entries!