Transcript c - Agenda INFN

Optoelectronics Laboratory
Polytechnic of Bari
(Italy)
PHOTONICS IN SPACE
Caterina Ciminelli and Mario N. Armenise
Dipartimento di Ingegneria Elettrica e dell’Informazione
Politecnico di Bari - Italy
V LNL NATIONAL COURSE
15-19 April 2013
INFN Legnaro
OUTLINE
INTRODUCTION
ADVANTAGES OF PHOTONIC SYSTEMS AND DEVICES IN SPACE
SPACE APPLICATIONS
OPTICAL SIGNAL PROCESSORS
PHASE COMPARATOR
OPTICAL PRE-PROCESSOR FOR REMOTE SENSING
ACOUSTO-OPTIC SPECTROMETER
INTEGRATED OPTICAL DEVICES FOR SAR APPLICATIONS
PHOTONIC CRYSTAL CAVITIES
HIGH-Q RESONATORS
SINGLE RING, MULTI RING CONFIGURATIONS
VERTICALLY STACKED COUPLED RING RESONATORS
INTEGRATED OPTICAL GYROSCOPES
E-FIELD SENSORS
PHOTONIC/ PLASMONIC COMPONENTS
NANOPARTICLES DETECTION AND SIZING
CONCLUSIONS
INTRODUCTION
OVER THE LAST 20 YEARS PHOTONICS HAS ADVANCED AND MATURED
INTEGRATED PHOTONIC DEVICES HAVE BEEN DEVELOPED
APPLICATIONS IN HARSH ENVIRONMENTS
EX.: PRESSURE SENSING IN OIL WELLS,
TEMPERATURE SENSING IN FURNACES
SENSING IN HIGH RADIATION ENVIRONMENTS
QUANTUM PHOTONICS HAS IMPLEMENTED PHOTONIC CHIP-BASED GATES
TO REALIZE LOGIC CIRCUITS AND STUDY QUANTUM EFFECTS
THIS PLATFORM ALLOWS ALSO
TO STUDY RELATIVISTIC EFFECTS ON QUANTUM MECHANICS
INTEGRATED PHOTONIC SPECTROGRAPHS
STELLAR INTERFEROMETERS
MICRO AND NANO PHOTONICS HAVE MANY
ADVANTAGEOUS FEATURES FOR APPLICATIONS IN SPACE
THROUGH THE COMBINATION OF MICRO, NANO,
INTEGRATED-OPTIC AND FIBER-OPTIC TECHNOLOGIES.
HERE I WILL PRESENT SOME SELECTED APPLICATIONS
FOR SPACE. THE PURPOSE IS TO PROVIDE SOME
EXAMPLES OF TECHNICALLY-FEASIBLE CONCEPTS, AND
THEIR SIGNIFICANT BENEFITS FOR SPACE SYSTEMS.
THE SPACE ENVIRONMENT
MOST OF SCIENTIFIC EXPERIMENTS ARE IN LOW EARTH ORBIT
200-2000 KM
EX: : HUB SPACE TELESCOPE (570 KM), ISS (360 KM)
AT THESE ALTITUDES (THERMOSPHERE/EARLY EXOSPHERE)
THE PRESSURE IS 3X10-8 AND 2X10-10 mbar
THE TEMPERATURE RANGES FROM 73 TO 323 K
CONSTANT BOMBARDMENT OF RADIATION AND PARTICLES OCCURS
Advantages of the photonic systems in Space applications
 reduced losses
 increased resistance to electromagnetic interferences,
electric discharges and charged particles
 more compact on board arrangement and consequent
design of the systems taking into account the failure
probability
high transmission rate
optical isolation of on-board critical subsystems
high speed optical processing of RF and microwave
signals
on-board processing for real-time services
reduction of number of links towards the ground stations
 reduction of costs
Advantages of the guided-wave photonic devices
 wide bandwidth
 parallel signal processing
 high transmission velocity
 scalable multiplexing and demultiplexing
 immunity to the electromagnetic interferences
and electric discharges
 reduced weight and volume
 high reliability
Characteristics required to the micro and nanophotonic
technologies
 use of various materials
 capability of realizing miniaturized photonic devices
 compatibility with other technologies
 technological process compatibility for fabricating
several functional blocks
 devices stability in Space environment
Space Applications
OPTICAL SIGNAL PROCESSORS
MULTICHANNEL SENSOR SYSTEMS’
RF SIGNAL OPTICAL LINKS
NAVIGATION
SPACE ACTIVITIES
EARTH OBSERVATION
TELECOMMUNICATIONS
RADAR SURVEILLANCE
Earth observation
Main requirements of the systems are
the information management and commercial benefits
Joint use of tlc and observation techniques allows several services in
both civil and military fields, e.g. crisis and disaster management.
SAR applications would significantly benefit of optical devices
because the synthesis of an object image, obtained by correlating the echoes
of a radar signal with a reference signal is equivalent to the optical
reconstruction of the Fresnel diffraction pattern of the same object when
illuminated with coherent light
Telecommunications
Strong demand for low cost systems and interactive services
ex. : scanning spot beam antenna able to increase
the number of narrow beams covering different
areas on tdma basis and to shape the beam for specific areas
The use of integrated optical technology can really improve
the cost/performance figure for phased array antennas
because of the strong reduction of the hardware
Radar surveillance and navigation control
Radar surveillance can also benefit of the characteristics of
guided-wave devices, such as reduced size, weight and cost
Photonic devices can be used in systems for air traffic control,
based on satellites with large phased array antennas
electronically scanning the area under control continuously
varying the beam pointing
OPTICAL SIGNAL PROCESSORS
Ti:LiNbO3 electro-optic guided-wave phase comparator
1990
Optical pre-processor for remote sensing
1998
Acousto-optic spectrometer
1995
Integrated optical devices for SAR applications
Patented acousto-optic SAR correlator
1988
Carrier frequency: 10 GHz
Bandwidth: 50 MHz
Optical wavelength: 840 nm
Average distance of the target: 10 km
Bragg cell length: 1 cm
Azimuth resolution: 3 m
CCD matrix: 800 x 800
Integrated optical devices for SAR applications
Acousto-optic correlator for SAR image reconstruction
AlGaAs/GaAs; Ti:LiNbO3
Carrier frequency: 10 GHz
Bandwidth: 50 MHz
Average distance of the target: 10 km
Optical wavelength: 850 nm
Bragg cell length: 1 cm
Azimuth resolution: 45 cm
Range resolution: 126 cm
CCD matrix: 800 x 800
Transducer bandwidth: 210 MHz
Bragg cell center frequency: 650 MHz
1992
PHOTONIC CRYSTALS FOR SPACE
APPLICATIONS OF PHCs
• IR detectors
• Microcavities for sensing
• (UV) Radiation shielding
• Optics for space telescopes
• Solar cells
• Antenna parabolic mirrors
• Power lasers for power beaming
• VCSELs
Photonic crystal optical fibers
• PhC Optical fiber gyros
• Beam forming with PhC optical fiber
PHOTONIC CRYSTAL CAVITIES
2004
PhC microcavity for filtering and sensing
Study of tunability mechanisms
2006
2006
Analysis PhC Fabry-Perot extended cavity by the Green function
z
Load SiO2
Core Si
y
x
nload
ne
Substrate SiO2
Geometrical Parameters
nsub
Value
Core thickness [μm]
0.34
Load layer thickness [μm]
0.1
Lattice constant [μm]
0.38
Hole radius [μm]
0.148
Cavity length [μm]
8
2010
Coupled cavities
By increasing the number of the
coupled resonant cavities:
 isolation among
channels increases
 flatness decreases
2005
Optical links
Fiber optic links for high speed data
transmission to be included in a new
processing architecture for
SAR applications
2012
HIGH Q RING RESONATORS
Optical ring resonator modelling
Transfer function
FSR
Q-factor
(a  1)
FWHM
depends on a, t and L
Three coupled microcavities
 Study of multi-ring resonator for sensing applications
2008
Triple ring resonator
Single ring configuration
Triple ring configuration
Ei1
Ei2
Ei1
Ei2
Ed1
Ed2
Ed1
Ed2
Δν d
SFS 

Ω λ0
The scale factor depends only on the resonator
footprint and the operating wavelength.
SFT 
Δν dmax

K
Ω
λ 0 Enhancement factor
The scale factor can be enhanced by properly
optimizing the coupling efficiencies.
ηINT  0.1
ηINT  0.01
dmax
SFT 
K
λ0
ηINT  0.2
ηINT  0.05
The scale factor enhancement occurs only when ηEXT > ηINT.
Keeping constant the footprint, the scale factor is magnified of 83% by using the TRR
instead of the single ring resonator.
ηINT  0.0110
ηEXT  0.3811
ηINT  0.0110
ηEXT  0.3110
ηINT  0.0110
ηEXT  0.0110
-The TRR-based RMOG is very linear in a wide range of Ω values (0÷100 rad/s).
-TRR-based RMOG is a very promising device with several applications in aerospace
Two integrated optics vertically stacked ring resonators
Light manipulation
•
•
A couple of ring resonators stacked on top of each other in integrated optics (SOI
technology)
Excitation and extraction coupling is obtained through a bus waveguide laterally
coupled to the stack
input
through
2010
Optical pulses having superluminal velocities
have been experimentally demonstrated
Integrated optical cavities
can be used as slow or fast light structures
For the first time, a theoretical investigation
of group velocity manipulation device formed by
two vertically-stacked micro-ring resonators and
a straight bus waveguide, has been recently published
by our Group
optical power is periodically exchanged
between the rings and supermodes are excited
The device behaves as on optical cavity
with a wavelength-dependent transmittivity
Launching an optical pulse into the input port,
it propagates within the vertically-stacked rings and
comes out from the device through port
The spectral response is calculated as
the wavelength-dependent ratio between
the optical power at the two ends of the straight bus
waveguide (input and through ports)
For each polarization,
the two coupled rings support two supermodes,
which are eigensolutions of the Helmholtz equation
According with the coupled mode theory,
the two supermodes
can be obtained as a linear combination of the modes
supported by the two uncoupled rings
Spectral response at the through port
2
T     
he
i L
e  e
L
 i L
2 
e  cos  L  e 


2 i L
L
 1    e
i L  L

2

cos  L 
h is the portion of the input optical amplitude
that is coupled to the bottom ring,
τ is the portion of the input optical amplitude
remaining in the bus waveguide
2
Spectral response
CMT
If κ = 0 and cos(κ L) = 1
the spectral response is the same
of a single ring resonator coupled to a bus waveguide
When cos(κ L) <1, for each resonance order
two resonance minima
appear in the spectral response
The magnitude of the splitting between these two minima
increases as cos(κ L) decreases
CONTROLLING GROUP VELOCITY 10
Grid of eigenvalues
For each m value the resonator exhibits
two resonance wavelengths.
Only for κ = q π / L
at each resonant order corresponds
only one resonance wavelength,
i.e. the degenerate mode condition is obtained
Spectral response
The envelope of the optical pulse moves at the group velocity vg = c / ng ,
and the pulse distortion depends on the group velocity dispersion
If ng < 1 we have vg > c or negative
if ng > 1 we have vg < c
derivative of ng with respect to λ is a measure of pulse distortion
Group index of the resonant cavity depends on λ
and on the two key parameters h and κ
By properly tuning these last two parameters,
vg can be effectively manipulated,
which means that two degree of freedom are
available in group velocity tuning
Slow and fast light in two vertically stacked ring resonators
FAST LIGHT REGIME : ng < 1 (vg > c)
SLOW LIGHT REGIME: ng > 1 (vg < c)
ng > 1 (vg < c)
ng < 1 (vg > c)
Ring resonators materials properties
FCL*
[dB]
RC*
[mm]
DW*
ACT*
Wavelength
In* Loss
[dB/cm]
Tuning
Materials
Polimers
VIS*-NIR*
0.1 - 2
0.1-0.5
20 -5
TO*,EO*
12’’
dyes
Ion exchange in
glass
VIS*-NIR*
< 0.1
< 0.2
20
(TO*)
3’’
APR*
SOS*
VIS*-NIR*
< 0.1
0.1 – 2
20 – 2
(TO*)
4’’
Er+
InGaAsP/InP
1.3/1.5 mm
0.1 - 2
1–5
1 – 0.005
TO*, EO*
2’’
in*
GaAlAs/GAs
0.8 mm
0.5 - 2
1–5
1 - 0.1
TO*, EO*
3’’
in*
LiNbO3
NIR*
< 0.3
<1
20
(TO*), A*
4’’
no
SOI*
NIR*
< 0.5
1-5
0.005
TO*,(EO*)
4’’
no
SiNx / SiONx
VIS*-NIR*
0.1 - 20
0.2 - 2
0.1- 1
TO*
-
no
(*) SOS = Silica on Silicon; SOI = Silicon on Insulator; FCL = Fiber coupling loss; RC = Critical radius;
DW = Wafer Dimension; ACT = Active material; NIR = Near Infrared; VIS = Visible; TO = ThermoOptical; EO = Electro-Optical; A = Acoustic waves; APR = A Priori inclusion within matrix; in =
intrinsic
Integrated optical gyroscopes
Semiconductor Ring Laser (SRL): sensing element
Active GaAs-based photonic integrated circuit
for angular rate sensing
(patented configuration)
Quantum effects investigation
Lock-in effect and mode competition limit preformace of this gyro
Lasing outside the sensing element
2001
Passive
architecture
Passive ring resonator gyro
Optical fibre
Optical fibre
Optical fibre
2005
Optical fibre
Low-loss Silica-on-Silicon
integrated resonator having a
length of 42 cm to be included in
a passive integrated optical gyro
Experimentally
measured response
Through
Drop
InP fully integrated optical gyroscope
InP PIC
DFB
2009
Main advantages




Size and weight reduction
Thermal effects limitation
Reliability increase
Cost decrease
PIC for
angular rate sensing
Basic building blocks
InP ring resonators fabricated at HHI
Fabricated chip
ring
bus waveguide
High-Q InGaAsP/InP resonator
Q - factor heavily depends on propagation loss experienced by the resonant
mode within the resonator
Investigation of ring waveguide scattering loss
w  700  1100 nm
 InP 
3.45  y = 0.76, x = 0.34  


3.361  y= 0.55, x = 0.25   In1-x Ga x As y P1-y
 3.327  y= 0.45, x= 0.20  


n 2 = 3.168
n1 =
w = 1100 nm, h = 400 nm, Δn = 0.159, quasi-TE mode
2009
αSC = 0.3 dB/cm
High-Q InGaAsP/InP resonator
E-field sensors
Sensor allowing the simultaneous estimation of both module and phase of the field.
Bandwidth > 5 GHz and resolution < 1 mV/m.
The device is the basic building block of a sensors array for complex field distributions
mapping.
2011
Nanoparticles detection and sizing
NANOPARTICLE: if subjected to a light source, it acts as a scattering center (Rayleigh,
due to its small dimensions: R < λ/8) with polarizability α
CW (clockwise) and CCW (counter-clockwise) modes coupling + reservoir modes
2011
Sensor for nanostructured virus detection and sizing
From the transmission spectrum of
the resonator-virion system, the
device allows to derive the size of
nanoparticles having a radius in the
range 30 - 100 nm.
2013
Conclusions
SOME SIGNIFICANT PHOTONIC DEVICES FOR SPACE
APPLICATIONS
OPTICAL SIGNAL PROCESSORS
OPTICAL LINKS
NAVIGATION DEVICES
PHOTONIC CRYSTAL CAVITIES
MICRORESONATORS
Advantages of photonic devices in space-based systems
Low size, due to short wavelengths, means reduction of payload mass and
of launch and satellite cost
Low loss, due to the high value of the efficiency, means low power consumption
and then reduced size of the number of solar cells, of the batteries weight
and of the satellite weight and overall cost
Improved em compatibility, which allows the instrumentations to be operated in
small volumes
Reduction of data to be transmitted to ground stations , if on-board optical
pre-processing is activated with a consequent reduction of the space
segment cost (ground side)
On-board processing, which allows to deliver data collected by the satellite to a
large number of customers