ServalPlus
Master Laser Power Amplifier System
Littman/Metcalf Master Laser
Tapered Amplifier Technology

Scientific Lasers

TEC 420

Vorsprung durch Innovation

Cavity ModesThe emission wavelength of a laser isdefined by two features. The first condition is the cavity mode. The second condition is the amplification
range of the gain medium. Since
diode lasers have an extremely wide
gain region, it is necessary to put awavelength selective medium insideof the cavity like a grating. In order totune such a laser modehop-free, it isrequired to synchronize the grating
defined wavelength with the cavity
defined wavelength [1].

Grating

Wavelength

Pivot Point
x1

Laser

Tuning Mirror

x2

Grating

Outline
356mm

Technical Realization

35dB

214mm

Tapered Amplifier

Littman / Metcalf
Master Laser
Optical Isolator
60dB

Technical Solution
Sacher Lasertechnik has realized thesynchronization between grating defined and cavity defined wavelength
by only a simple rotation of the mirror.
The adjustment of the pivot point isdone during the wavelength scanning
operation of our
Littman/Metcalf laser
system according to our patent
5,867,512 application. Due to thisspecial method, we are able toensure the best modehop-free tuning
behavior of our laser system with thehighest power available.

x3

Optical Isolator

Physical Basics

Sacher Lasertechnik has combined
its Littman/Metcalf tunable diodelaser with a tapered amplifier. This
results in a stable, narrow linewidth,
wavelength tunable high power
laser source for spectroscopy, opticalcooling and trapping. The low linewidth below 500kHz of the Littman/
Metcalf design together with theexcellent beam stability results in asuperior laser source.
[1] M. G. Littman, H. J. Metcalf, Appl. Opt. 17, 2224, 1978

Spectral Quality

10Signal [dB]0-10

Beam Quality-20-30-40-50
760

770

780

790

800

Wavelength [nm]Red curve:

TEC-420 without masterBlack curve: Injected master laser at
different wavelengths

Typical Values
Power: 500 mW ... 2500mW
2M < 1.7Specifications
Output Power500 mW .. 2500mW (depending on wavelength)

Wavelength

650nm, 670nm 735nm, 765nm, 780 nm, 795nm, 830nm, 850nm
935nm, 960nm, 1010nm, 1060 nm, 1080nm, or specified

Linewidth (50ms)< 0.5MHz, typ. 0.3MHz

Linewidth (20s)<Long Term Drift (24h)Typical < 300MHz

Side Mode Supression> 40 dB for a normal ECDL

Beam Waist (2 w0)

2.5 mm x 2.5 mm (typ.)Beam Divergence< 2 mradBeam Quality M 2

M² < 1.7

Coarse Tuning Range

10nm .. 40nm

Fine Tuning / Mode-Hop free

250GHz / 30 GHz .. 100 GHz

Polarization

Linearly > 1000:1

WeightLaser Head: 2.6 kg, Power Supply: 9.5 kg

Laser Head Dimension (W x L x H)

214 x 356 x 119 mm

5MHz, typ.

2MHzApplication Example
Saturated Absorption Spectroscopy
High resolution spectroscopy requires laser features like narrow linewidth, highpassive stability, exact adjustable wavelength as well as an excellent fine tuningability. The schemaic shows a MOPA setup. It includes a Littman/Metcalf masterlaser, tapered amplifier, optical Isolators as well as fiber coupling. Theoscilloscope trace on the left hand side shows the cross-over transition of theD2-line of Rubidium.

About Sacher Lasertechnik
Company Profile
Sacher Lasertechnik is leading manufacturer of tunable external cavity diode lasers(ECDLs) with more than 10 years of experience. The product range includes antireflection coated diode lasers, ECDLs in Littrow and in Littman/Metcalf configuration
as well as driver electronics for the LD and sophisticated measuring electronics.
Please contact us with your measurement requirements. We would be proud
to support you with our competence

Please contact us
Sacher LasertechnikGmbH
Rudolf-Breitscheid Str. 1-5
D-35037 Marburg/LahnGermany
Tel.: +49 6421 305 - 0
Fax: +49 6421 305299

Sacher Lasertechnik Email: contact@sacher-laser.com
Web: http://www.sacher-laser.com
LLC5765 Equador Way
Buena Park, CA90620
U. S. A.
Tel.: 1-800-352-3639
Fax: 1-714-670-7662