UNCLASSIFIED. Photonic-Crystals In Military Systems Energy Harvesting, Thermal Camouflage, & Directed Energy. Leo DiDomenico 3 Hwang Lee 1 Marian Florescu 1 Irina Puscasu 2 Jonathan Dowling 1. 1 Department of Physics & Astronomy, Louisiana State University 2 Ion Optics Inc.
Photonic-Crystals In Military Systems
Energy Harvesting, Thermal Camouflage, & Directed Energy
1 Department of Physics & Astronomy,
Louisiana State University
2 Ion Optics Inc.
3 Xtreme Energetics Inc.
Points of Contact: Dr. Leo D. DiDomenico Leoddd@XEsolar.com & Prof. Jonathan P. Dowling firstname.lastname@example.org
Conventional TPV Systems Too Hot
Optimize the input radiation band and propagation direction to a PV & don’t worry too much about the PV itself!
TPV using PBG is relatively Low Temperature.
S. Lin et al. Sandia Labs
Thermal signatures have become too easy to detect
Thermal Radiation Control Designs
for adaptive thermal emissivity response.
Photonic Crystal Lasers for Power Beaming
Defense against kinetic energy weapons requires
repeated fast interception. Chemical lasers fail to
deliver the punch over an extended fight.
Gas Dynamic lasers require energetic chemical reactions which limit practical embodiments
Convert heat gradients into
A flow of incoherent narrow band pump light for laser using PBG energy funnel.
Joannopoulos, Meade, Winn, Photonic Crystals (1995)
Each scattering site contributes to the total
The math can be very complexbut the basic idea is VERY SIMPLE...
Scattered waves can add destructivelyfor some frequencies and from somedirections…
Therefore, certain very special PBG structures have all directions of propagation forbidden over a band of frequencies.
3D Crystal Structure with scattering plans shown
New Design Tools are Needed for Opto-Thermal Engineering with Photonic Crystals
The fields do not always
overlap the dielectric whereatoms can absorb or emit energy & heat the material.
An extension of basic radiation theory, which now includes photon-phonon
interactions inside a PBG material with a non-uniform temperature distribution, is being developed by the authors and with the intent of develop engineering software tools for opto-thermal PBG materials.
Semiconductors for Light
Optical Switching & Routing
Strong Nonlinear Optical Effects
Negative index metamaterials for stealth applications
and super-prism dispersion, true time delay lines
There are 2 potential solutions Using Photonic Crystals …
Out of band energy from PV cell,creates waste heat but no electricity !
Band GapLight Cone
RethermalizeOut of Band Energy
Now extend principles to a PBG material
TPV Cell Device
Funnel(Not a Filter)
Broad BandHeat Source
Improve conversion efficiency:
Incorporate PBG into a Classic TPV Design
Solid angle for absorber
Solid angle for the sun
Temp of the thermal source
Temp of absorber
TA = 2500 K
Temp of the cell
Instead of increasing WS (concentration), decrease
the solid angle of the intermediate absorber, WA.
Novel Design of an efficient angle-selective PBG absorber
Blackbody input radiation
Filter output radiation
Filter output radiationFunneling of the Thermal Radiation
5 % Transfer efficiency
20 % Transfer efficiency
Blackbody input radiation
width of the rectangular veins (optimum values: r/a=0.078, L/a=0.194 and w/a=0.38)
lower frequencies (high transmission)
Photonic crystal structure Photonic band structure
refraction dielectric or in the air fraction
structure in order to enhance thermal emission
Electromagnetic field distribution for TM modes for the first three bands at the M-point
Normalized emission from photonic crystal test structure at 325 C under different gas conditions: different concentration values for CO2 and N2. (right side-zoom in)
Possibility of tuning the emissivity of the structure by gas choice and by controlling its gas concentration
Laser GainMediumEnergy Separation - I
Schematic of energy flow:
Three types of insulators are possible: electrical, thermal, & light. We are using the light insulating properties of Photonic Crystals to force the desired narrow-band photons into the Lasing gain medium & rethermalizing the remaining out-of-band photons into the desired band for further extraction.
Designing thespectral and directionalProperties of PCS is ahard synthesis problem.
512 node, dual-processor IA32 Linux cluster with 3.06 GHz Intel Pentium IV Xeon processors and 2 GB RAM
Super- Mike LSU
New, $4.6M, world-class, JEOL JBX-9300FS e-beam lithography system (third of its kind)
Spectral and angular optical FTIR characterization facilities
Ion Optics Inc.
Thermal Radiation Control in IR
Enhancement and suppression of thermal emission by a three-dimensional photonic crystal, Lin et al. (2000) Sandia Labs
Photonic-crystal enhanced narrow-band infrared emitters, Pralle et al. (2002) Ion Optics
Three-dimensional photonic crystal emitter for thermophotovoltaic power generation, Lin et al.,(2003) Sandia Labs
Thermal emission and absorption of radiation in finite inverted-opal photonic crystals, Florescu et al.,(2005) JPL&LSU
Direct calculation of thermal emission for three-dimensionally periodic photonic crystal slabs, Chan et al.(2006) MIT
BB, Pin = 315 mW, T2 = 420.1 oC
BB (273.4oC) and PC (273.4oC) plots have the same input power while the photonic crystal produces lower wavelength photons
PC, Pin = 130 mW, T2 = 420.1 oC
BB, Pin = 130 mW, T1 = 273.4 oC
BB (420.1oC) and PC (273.4oC) plots have the same peak power wavelength
JPL (micro-fab), Ion Optics (testing), LSU (analysis)