Stabilized
Fiber Link(SFL)The Stabilized Fiber Link (SFL) is alength-stabilized, dispersion-compensated optical link for the timing distribution system, comprising the subunits
Fiber Link Stabilization Unit (FLS) andLink Fiber Connection-Receiver (LFCReceiver). With an attosecond precisionphase detector, actuators, and SYNCRO
locking electronics, the FLS unit on
the system reference side includes allnecessary components to stabilize thelength of the optical fiber link. The LFCReceiver on the client side consists ofa dispersion compensation module anda bi-directional optical amplifier. Theamplifier at the end of the link ensuresthe level of output power as required forthe clients. Part of the signal is reflectedback through the link to provide feedback on any length changes.

A p p l i c at i o n s
Low-drift and low-jitter
distribution of opticalsignals over larger distancesStabilized Fiber Link (SFL)

Optical fiber link:
Parameter

Value

Comment

GENERAL SPECIFICATIONS

S p e c i f i c at i o n s :Optical link stabilization unit:
Parameter

Comment

Fundamental design frequency

50 – 250 MHz

to be specified prior to system order

Added timing jitter<10 fs*RMS [3 Hz, 10 MHz]

Added timing drift<10 fsRMS over eight hours, measured with balanced crosscorrelator, out-of-loop measurement

Timing resolution<300 asdetection noise floor of integrated timing jitter[1Hz,10MHz]

GENERAL SPECIFICATIONSOPTICAL inPUT
Optical power>20 mW

Pulse duration<200 fs

Input connector

SC/APC

Fiber optic specifications

ITU-T G.652.D compliant

Effective link length<400 mDispersion compensation

DCF spool

DCF spool connectors

SC/APC

Wavelength

1560 nmCentral wavelength tolerance±20 nmAverage power>10 mW

Pulse duration<300 fs

Output port typeFree space or fiber coupled

Er-doped amplifier to compensate for link losses<1 mW

fiber-coupled (SC/APC), suitable to measure the optical
spectrum of the laser by an external OSA

utility and environmental requirements
Ambient temperature

20 – 25 °C

Temperature variation±2 °C

for full specifications; pertains to all link components
except the FLS unit** The compensation of the optical links has to be done “in the field“. The length of the DCF spools will be prepared based on link lengthmeasurement data to be provided.

ParameterValue

Comment

generalLink end point
FWHM, Gaussian, interferometric autocorrelation

SMA connector

utility and environmental requirements
Ambient temperature

20 – 25 °C

Temperature variation±100 mKfor full specifications; pertains to FLS unit only

Length of connecting cable

10 m

Between FLS unit and SYNCRO-FLS

Integrated feedback

SYNCRO-FLS

Menlo SYNCRO Platform, optimized for fiber link stabilization

yesmatched lengths of DCF and SMF**

Optical fiber link output on client side:

electrical output>100 mVMonitor output port

SMF28+

FWHM, Gaussian, interferometric autocorrelation

opticaL OUTPUT at client side

Auto lock

SC/APC

In-loop link amplifier
ValueHigh sensitivity error signal

Input/output connectors

Automatic (re-)lock algorithm in SYNCRO-FLS

remote control
Control system interfaces front-end

USB/RS232

Interface to SYNCRO-FLS

Control system interfaces back-end

USB/RS232/Ethernet

Interface to LFC-receiver*full specifications only if the temperature stability of the environment is within specified range

partially reflective Faraday rotating mirror

version 1: optical free space output***
Pulse length<300 fs

Average output power>10 mW

Optical amplitude stability<0.1 %

Optical bandwidth>10 nmCentral wavelength

1560 nmCentral wavelength tolerance±20 nmBeam diameter

>1 mm

FWHM
RMS [1kHz-10 MHz]version 2: optical output fiber coupled***Pulse length<300 fs

Average output power>10 mW

Optical amplitude stability<0.1 %

Optical bandwidth>10 nmCentral wavelength

1560 nmCentral wavelength tolerance±20 nmOutput connector

SC/APC

FWHM; the real value has to be the same for all lines
RMS [1 kHz, 10 MHz]***Decision on either Version 1 or 2 for each of the links has to be made eight weeks prior to the start of manufacturing

m e a s u r e m e n t data :Out-of-loop long term timing drift between two stabilized fiber links:

Out-of-loop power spectral density (PSD) (black line) and integrated timing jitter (red line) between two stabilized
fiber links:

Menlo Systems GmbHAm Klopferspitz 19aD-82152 Martinsried
Germany
T+49 89 189 166 0
F+49 89 189 166 111
sales@menlosystems.com

www.menlosystems.com

Menlo Systems, Inc.
56 Sparta Avenue
Newton, NJ07860
USA
T+1 973 300 4490
F+1 973 300 3600
ussales@menlosystems.com

Thorlabs, Inc.
56 Sparta Avenue
Newton, NJ 07860
USA
T+1 973 579 7227
F+1 973 300 3600
sales@thorlabs.com

D-SFL-EN 13/01/18