Vorsprung durch InnovationLB2001 & LB2005
Servo Controller
Electronic Systems & Devices
Pound Drever Hall Locking Scheme- High Speed Servo Controller - Modulator Demodulator
LOCKING SCHEMES
Side Of FringeTop Of FringePound Drever HallBjorklund
MOT & REFERENCE CELLS
Rubidium Cesium
Potassium Lithium
Optical Cooling & TrappingUltrastable Laser Systems
0.05
0.10
0.15
0.20
0.25
-500 -400 -300 -200 -100 0 1000.09
0.10
0.11
0.12
Bala
nce
d S
ignal [
mV
]
156.95 MHz 266.65 MHz
F=3
F=2 co 3
F=1 co 3
F=2
F=1 co 2
Lase
r T
ransm
issi
on [ m
V ]
Frequency [ MHz ]
87Rb : 5S
1/2, F=2 - 5P
3/2 F=
F=1
-0.1
0.2
0.3
0.4
0 2 4 60.04
0.06
0.08
0.10
0.12
0.14
87RB: 5S
1/2, F=1 - 5P
3/2, F=0,1,2
85RB: 5S
1/2, F=2 - 5P
3/2, F=1,2,3
85RB: 5S
1/2, F=3 - 5P
3/2, F=2,3,4
Bala
nce
d S
ignal [
mV
]
6.834 GHz
87RB: 5S
1/2, F=2 - 5P
3/2, F=1,2,3
3.035 GHz
Lase
r Tra
nsm
issi
on [ m
V ]
86420-4-6-820
30
40
50
60
70
8050-5
-50
0
50
200
La
ser
tra
nsm
issi
on
[ m
V ]
5.170 G Hz 4.021 G H z
62P
1/2,F=3 - 6
2P
3/2,F=[3 ,4 ,5 ]
Ba
lan
ced
sig
na
l [ m
V ] 6
2P
1/2,F=4 - 6
2P
3/2,F= [2 ,3 ,4 ]
-400 -200 0 200 400
0.03
0.04
0.05
0.06
0.07
-400 -200 0 200 400
0.10
0.15
0.20
0.25
La
ser
tra
nsm
issi
on
[ m
V ]
Re lative Frequency [ M Hz ]
F= 3
F= 4 co 5
F= 4
F= 3 co 4
F= 3 co 5
F= 3
133C s-D 2 : 6
2P
1/2,F=4 - 6
2P
3/2,F=
Ba
lan
ced
sig
na
l [ m
V ]
133D2 Transitions in Rb, central wavelength 780.27nm D2 - Transitions in Cs, central wavelength 852.347 nm
0
50
62P
1/2,F=3 - 6
2P
3/2,F=[3 ,4 ,5 ]
an
ce
dsi
gn
al[m
V
6 P1/2
,F 4 6 P3/2
,F [2 ,3 ,4 ] 200
V]
62P F=4 - 6
2P F=[2 3 4]
0.2
0.3
ance
d S
ignal [
m 3.035 GHz
0.4
mV
]
6.8334 GHz
Scientific Lasers
Side of Fringe Type of Lock
Application Examples
Several types of laser stabilization schemes are known in literature. We summarized some of the most common types of locking schemes as block diagram.The oscilloscope screen shot shows a typical view of the specroscopy, before
Pound Drever Hall Type of Lock
Bjorklund Type of Lock
Rubidium D2 Line
Rubidium D2 Line
Rubidium D2 Line
Saturated Rb Spectrum
Red Curve:Saturated Rb Spectrum
Green Curve:Phase Modulated Spectrum
Red Curve:Saturated Rb Spectrum
Green Curve:RF Modulated Spectrum
applying the lock.
Product Features
Modulator Demodulator (Pound Drever Hall)
Modulation Frequency 1kHz .. 100MHz
Phase Delay 0° .. 360°
Modulation Amplitude up to 0dBm
Modulation Amplitude up to 20dBm (optional)
Input Impedance 50W (Photodetector)
Output Impedance 50W (RF Modulation)
Output Impedance 50W (Error Signal)
Frequency Generation 2 x DDS
Internal Data
Processor 300MHz FPGA
System Clock 3GHz
System Bandwidth up to 100MHz
Common Data (General)
Dimension (WxHxD) 270 x 110 x 320 mm
Weight < 5kg
Line Voltage 115V / 230V +/- 10%
Line Frequency 50 .. 60Hz
Warm-up Time 10min
Storage Conditions -25 .. 70°C
Operating Temperature 0 .. 40°C
Servo Controller (Lockbox)
PI Corner Frequency (high) 1Hz .. 1MHz (HF Path)
PI Corner Frequency (low) 1 Hz .. 100kHz (LF Path)
Amplification -40dB .. +40dB
Input Impedance 1MW
Output Impedance (high) 50W
Output Impedance (low) 1MW
Low Frequency Limit
Integration Hold Mode
Internal Data
Processor 300MHz FPGA
D/A Converters sleeping mode
System Bandwidth 10MHz
Interface USB
Remote Control Software Package
Flexibility
Stand-Alone Unit
Laser Manufacturer independent
Common Data (Remote Control)
High speed FPGA controlled proportional integral (PI)
servo controller for external cavity diode laser systems
as well as DFB diode lasers. Model LB2001 allows to
stabilize the laser frequency via piezo- and laser current
feedback path.
High frequency Modulator/Demodulator for Pound
Drever Hall type of lock. Model Lb2005 is prepared for
ooperation with the Servo Controller LB2001 for
generating a Top of Line type of lock.
Both Models enable an easy, intuitive and highly stable
Top of Line type of lock.
Specifications
The graph shows the effect of applying the high bandwidth type of lock to the noise figure of the laser system. The red curve show the noise figure of a free running DFB laser. The green curve shows the noise figure of the locked DFB laser. This significant reduction of the RIN noise results into a linewidth narrowing of the laser.
Sacher Lasertechnik is leading manufacturer of tunable external cavity diode lasers (ECDLs) with more than 20 years of experience. The product range includes anti-reflection 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.
Noise Reduction and Linewidth Narrowing
Application Example
Company Profile
About Sacher Lasertechnik
Please contact us
Sacher Lasertechnik
R. Breitscheid Str. 1-5D-35037 Marburg/Lahn
Tel.: +49 6421 305 - 0Fax: +49 6421 305299
Sacher Lasertechnik
5765 Equador WayBuena Park, CA90620
Tel.: 1-800-352-3639Fax: 1-714-670-7662
GmbH
Germany
LLC
U. S. A.
Email: [email protected] Web: http://www.sacher.de
1k 10k 100k
-105
-100
-95
-90
-85
-80
-75
-70
-65
-60
-55
Comparison of noise spectra for 780nm DFB diodelaser
No
ise
Sp
ect
ra[d
BV]
Frequency [Hz]
free running locked
Sacher Lasertechnik Group