Photoreactive Organic Thin Films

Zouheir Sekkat, Wolfgang Knoll9780126354904, 0126354901

Photoreactive thin films have been investigated extensively due to the advances in photonics, and the coupling between photochemistry and nonlinear optics has developed into a new discipline over the last decade. Light can manipulate the orientation of optically sensitive chromophores containing polymeric thin films, and this phenomena has important applications to the field of opto-electronics and photonics especially in such areas as liquid crystals and optical storage of information. Scientists from different communities have been working in this area representing such fields as chemistry, chemical engineering, polymer science, and optics. The purpose of this books is to provide a comprehensive reference covering the basic fundamentals of the interdisciplinary research as well as the applications in photonics.Wolfgang Knoll is a former Directory of Polymer research at the Max Planck Institute. He is extremely well know for his research in this area. Zouheir Sekkat was a Postdoctoral researcher at Max Planck working under Professor Knoll. With Knoll’s involvement, we can be confident that the best people in this field will be contributing to the reference.

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Table of contents :
CONTENTS……Page 6
CONTRIBUTORS……Page 16
PREFACE……Page 20
I: PHOTOISOMERIZATION AND PHOTO-ORIENTATION OF AZOBENZENES……Page 22
1.1 Introduction……Page 24
1.2 The Azo Group……Page 26
1.3 Azoaromatics of the Azobenzene Type……Page 34
1.4 Azoaromatics of the Aminoazobenzene Type……Page 46
1.5 Azoaromatics of the Pseudo-Stilbene Type……Page 48
1.6 The Isomerization Mechanism……Page 52
1.7 Concluding Remarks……Page 59
2 Ultrafast Dyamics in the Excited States of Azo Compounds……Page 70
2.1 Introduction……Page 71
2.3 Results and Discussion……Page 73
3 Photo-Orientation by Photoisomerization……Page 84
3.1 Introduction……Page 85
3.2 Photoisomerization of Azobenzenes……Page 86
3.3 Photo-Orientation by Photoisomerization……Page 89
3.4 Photo-Orientation of Azobenzenes: Individualizable Isomers……Page 100
3.5 Photo-Orientation of Azo Dyes: Spectrally Overlapping Isomers……Page 104
3.6 Photo-Orientation of Photochromic Spiropyrans and Diarylethenes……Page 108
3.7 Conclusion……Page 117
APPENDIX 3A: Quantum Yields Determination……Page 119
APPENDIX 3B: Demonstration of Equations 3.12 through 3.15……Page 123
II: PHOTOISOMERIZATIQN IN ORGANIC THIN FILMS……Page 126
7.4 Transduction at “Command” Interfaces……Page 0
4.1 Introduction……Page 129
4.2 Photoisomerization of Azobenzenes in Molecularly Thin Self-Assembled Monolayers: Photo-Orientation and Photo-Modulation of the Optical Thickness……Page 131
4.3 Photoisomerization and Photo-Orientation of Azobenzenes in Supramolecular Assemblies: Photo-Control of the Structural and Optical Properties of………Page 138
4.4 Polymer Structural Effects on Photo-Orientation……Page 143
4.5 Pressure Effects on Photoisomerization and Photo-Orientation……Page 155
4.6 Conclusion……Page 161
5.1 Introduction……Page 166
5.3 Photoinduced Birefringence in Photochromic IsoSm* Copolymers……Page 173
5.4 Holographic Grating Recording……Page 181
5.5 Photoinduced Alignment of Low Molar Mass Liquid Crystals……Page 187
5.6 Photoaffected Phase Behavior and the LCPT Photorecording……Page 189
5.7 Conclusions……Page 193
6.1 Introduction……Page 200
6.2 Other Dyes Used in Photoactive LBK Films……Page 201
6.3 UV-Vis Spectroscopy as an Analytical Tool for the Investigation of Azobenzene LBK Film Structure……Page 204
6.4 Examples of the Influence of Structure on Photoisomerization……Page 207
6.5 Examples of the Manipulation of LBK Film Structure by Photoisomerization……Page 222
6.6 Examples of LBK Films with a Structure Tailored for the Desired Application……Page 231
6.7 Summary……Page 233
7 Electronic and Optical Transduction of Photoisomerization Processes at Molecular- and Bimoleculan-Functionalized Surfaces……Page 240
7.1 Introduction……Page 241
7.2 Electronically Transduced Photochemical Switching of Organic Monolayers and Thin Films……Page 242
7.3 Electronically Transduced Photochemical Switching of Enzyme Monolayers……Page 248
7.5 Recognition Phenomena at Surfaces Using Photoisomerizable Guest or Host Components……Page 267
7.7 Conclusions……Page 279
III: PHOTOCHEMISTRY AND ORGANIC NONLINEAR OPTICS……Page 290
8 Photoisomerization Effects in Organic Nonlinear Optics: Photo-Assisted Poling and Depoling and Polarizability Switching……Page 292
8.2 Photo-Assisted Poling……Page 293
8.3 Photo-Induced Depoling……Page 299
8.4 Polarizability Switching by Photoisomerization……Page 301
8.5 Conclusion……Page 304
APPENDIX 8A: From Molecular to Macroscopic Nonlinear Optical Properties……Page 305
9.2 Photoisomerization and Nonlinear Polarizability……Page 310
9.3 Alignment of Isomers in Polymers with Electric Fields……Page 314
9.4 Second Harmonic In-situ Investigation of Photoisomerization……Page 318
9.5 Conclusion……Page 324
10 Photoassisted Poling and Photoswitching of NLO Properties of Spiropyrans and Other Photochromic Molecules in Polymers and Crystals……Page 326
10.1 Introduction……Page 327
10.2 Molecular Second-Order Nonlinear Optical Polarizabilities of Photochromic Molecules……Page 328
10.3 Photoassisted Poling of Photochromes Other Than Azo Derivatives in Polymers……Page 336
10.4 Photoswitching of NLO Properties in Organized Systems and Materials……Page 342
10.5 Conclusion……Page 347
11 All Optical Poling in Polymers and Applications……Page 352
11.1 Standard Poling Techniques……Page 353
11.2 All Optical Poling……Page 355
12 Photoinduced Third-Order Nonlinear Optical Phenomena in Azo-Dye Polymers……Page 386
12.1 Introduction……Page 387
12.2. Third Harmonic Generation……Page 388
12.3 Electric Field Induced Second Harmonic Generation……Page 402
12.4 Degenerate Four-Wave Mixing……Page 409
12.5 Prospective and Conclusions……Page 413
IV: OPTICAL MANIPULATION AND MEMORY……Page 418
13 Photoinduced Motions in Azobenzene-Based Polymers……Page 420
13.2 Photoinduced Motions……Page 421
13.3 Possible Photonic Devices……Page 441
13.4 Conclusions……Page 444
14 Surface-Relief Gratings on Azobenzene-Containing Films……Page 450
14.1 Introduction……Page 451
14.2 Processes of SRG Formation……Page 453
14.3 Theoretical Models……Page 467
14.4 Factors Influencing the Formation of SRGs……Page 475
14.5 Open Questions and Challenges for the Near Future……Page 493
14.6 Possible Applications……Page 494
14.7 Final Remarks……Page 502
15.1 Introduction……Page 509
15.2 Photocontrol of Liquid Motion by Azobenzene Monolayers……Page 511
15.3 Photocontrol of Polymer Chain Organizations……Page 517
15.4 Photoinduced Motions and Mass Migrations……Page 522
15.5 Concluding Remarks……Page 530
16 3D Data Storage and Near-Field Recording……Page 535
16.2 Bit-Oriented 3D Memory……Page 536
16.3 Photochromic Materials for 3D Optical Memory……Page 538
16.4 Recording and Readout Optics……Page 545
16.5 Near-Field Recording……Page 555
16.6 Concluding Remarks……Page 559
17 Synthesis and Applications of Amorphous Diarylethenes……Page 563
17.1 Quasi-Stable Amorphous Diarylethenes……Page 564
17.2 Thermally Stable Amorphous Diarylethenes……Page 565
17.3 Optical Properties of Amorphous Diarylethenes……Page 567
17.4 Charge Transport in Amorphous Diarylethene Films……Page 571
17.5 Summary……Page 573
A……Page 575
B……Page 576
E……Page 577
N……Page 578
P……Page 579
S……Page 581
Z……Page 582