Derivative-free Optimization for Optical Chirality Enhancement
G. Pellegrini, F. Michelotti, A. Occhicone, M. Celebrano, M. Finazzi, and P. Biagioni
Chirality (In Nature)
Dipartimento di Fisica - Università di Pavia
Eosam 2024, 9-13 September 2024, Naples, Italy
Molecules
DNA
Proteins
Left Enantiomer
Right Enantiomer
Probing Chirality with Electromagnetic Fields
Dipartimento di Fisica - Università di Pavia
TM Polarization
Left = TE + i*TM
Right = TE - i*TM
Optical Rotation (OR)
Circular Dichroism (CD)
\[\mathrm{CD = A_{R}-A_{L}}\]
\[\mathrm{\psi = \Delta \theta} \]
TE Polarization
Eosam 2024, 9-13 September 2024, Naples, Italy
Superchiral Light: Enhancing Chiral Light-Matter Interaction
Dipartimento di Fisica - Università di Pavia
Finazzi, Marco, et al. "Quasistatic limit for plasmon-enhanced optical chirality." Physical Review B 91.19 (2015): 195427.
Schäferling, Martin. "Chiral nanophotonics." Springer Series in Optical Sciences 205 (2017): 159.
C = -\frac{\varepsilon_{0} \omega}{2} Im(\mathrm{\mathbf{E}}^{*} \cdot \mathrm{\mathbf{B}})
Mattioli, F. et al. Plasmonic Superchiral Lattice Resonances in the Mid-Infrared. ACS Photonics 7, 2676–2681 (2020)
Local optical chirality
Optical chirality enhancement
\frac{C}{C_{\mathrm{CPL}}}
Eosam 2024, 9-13 September 2024, Naples, Italy
Superchiral Light with a Planar Geometry
Dipartimento di Fisica - Università di Pavia
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Large optical chirality enhancement
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Uniformity over large areas
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Optical chirality switching
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Broadband operation
-
Flat spectral response
Planar Geometries as an Ideal Candidate
Eosam 2024, 9-13 September 2024, Naples, Italy
A Planar Geometry for Superchiral Light: Take 1
Dipartimento di Fisica - Università di Pavia
TE ± i*TM
TE ± i*TM
Surface Plasmon
Eosam 2024, 9-13 September 2024, Naples, Italy
A Planar Geometry for Superchiral Light: Take 2
Dipartimento di Fisica - Università di Pavia
Bloch Surface Waves (BSW)
TE ± i*TM
TE ± i*TM
\[ \mathrm{ (\lambda_{TM},\theta_{TM})} \]
\[ \mathrm{ (\lambda_{TE},\theta_{TE})} \]
\[ \mathrm{ (\lambda_{TM},\theta_{TM})} \neq \mathrm{ (\lambda_{TE},\theta_{TE})} \]
Eosam 2024, 9-13 September 2024, Naples, Italy
Aligning the Dispersion Relations
Dipartimento di Fisica - Università di Pavia
\[ \mathrm{ (\lambda_{TM},\theta_{TM})} \neq \mathrm{ (\lambda_{TE},\theta_{TE})} \]
Eosam 2024, 9-13 September 2024, Naples, Italy
\[ \mathrm{ (\lambda_{TM},\theta_{TM})} = \mathrm{ (\lambda_{TE},\theta_{TE})} \]
A Hard Earned Solution: SiO2-Ta2O5 1PDC
Dipartimento di Fisica - Università di Pavia
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Pellegrini, Giovanni, et al. "Chiral surface waves for enhanced circular dichroism." Physical Review B 95.24 (2017): 241402.
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Pellegrini, Giovanni, et al. "Surface‐enhanced chiroptical spectroscopy with superchiral surface waves." Chirality 30.7 (2018): 883-889.
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Pellegrini, Giovanni, et al. "Superchiral surface waves for all-optical enantiomer separation." The Journal of Physical Chemistry C 123.46 (2019): 28336-28342.
Eosam 2024, 9-13 September 2024, Naples, Italy
The Lazy Man Solution: Multi Objective Optimization
Dipartimento di Fisica - Università di Pavia
Eosam 2024, 9-13 September 2024, Naples, Italy
\omega_1 \, (\lambda_1)
\omega_2 \, (\lambda_2)
\begin{cases}
C(\omega_1) = -\frac{\varepsilon_{0} \omega_1}{2} Im(\mathrm{\mathbf{E}}^{*} \cdot \mathrm{\mathbf{B}}) \\
C(\omega_2) = -\frac{\varepsilon_{0} \omega_2}{2} Im(\mathrm{\mathbf{E}}^{*} \cdot \mathrm{\mathbf{B}})
\end{cases}
Maximize \(C \)
@ \(\omega_1\) and \(\omega_2\)
@ the 1DPC Surface
SIMULTANEOUSLY!!!
Band Alignement
Genetically Evolved (NSGAII) SiO2-Ta2O5 1PDC
Dipartimento di Fisica - Università di Pavia
Eosam 2024, 9-13 September 2024, Naples, Italy
SiO\(_{2}\)
Ta\(_{2}\)O\(_{5}\)
Vilfredo Pareto
Genetically Evolved Cellulose-Polystyrene 1PDC
Dipartimento di Fisica - Università di Pavia
Eosam 2024, 9-13 September 2024, Naples, Italy
Polystyrene
Cellulose
Genetically Evolved Low Contrast 1PDC
Dipartimento di Fisica - Università di Pavia
High Contrast
Ta\(_{2}\)O\(_{5}\)
SiO\(_{2}\)
SiO\(_{2}\)
SiO\(_{x}\)
Low Contrast
Eosam 2024, 9-13 September 2024, Naples, Italy
High vs Low Dielectric Contrast: Zooming in the Bands
Dipartimento di Fisica - Università di Pavia
High Contrast
Ta\(_{2}\)O\(_{5}\)
SiO\(_{2}\)
SiO\(_{2}\)
SiO\(_{x}\)
Low Contrast
Eosam 2024, 9-13 September 2024, Naples, Italy
High vs Low Dielectric Contrast: Reflection Maps for 1DPCs
Dipartimento di Fisica - Università di Pavia
High Contrast
Ta\(_{2}\)O\(_{5}\)
SiO\(_{2}\)
SiO\(_{2}\)
SiO\(_{x}\)
Low Contrast
Eosam 2024, 9-13 September 2024, Naples, Italy
High vs Low Dielectric Contrast: CD Enhancement
Dipartimento di Fisica - Università di Pavia
High Contrast
Ta\(_{2}\)O\(_{5}\)
SiO\(_{2}\)
SiO\(_{2}\)
SiO\(_{x}\)
Low Contrast
Eosam 2024, 9-13 September 2024, Naples, Italy
G. Pellegrini, F. Michelotti, A. Occhicone, M. Celebrano, M. Finazzi, and P. Biagioni
Towards Surface Mode Polarization Control
Dipartimento di Fisica - Università di Pavia
