This volume is a monograph on parallel optical interconnects. It presents not only the state­ of-the-art in this domain but also the necessary physical and chemical background. It also provides a discussion of the potential for future devices. Both experts and newcomers to the area will appreciate the authors' proficiency in providing the complete picture of this rapidly growing field. Optical interconnects are already established in telecommunications and should eventually find their way being applied to chip and even gate level connections in integrated systems. The inspiring environment of the Basic Research Working Group on Optical Information Technology WOIT (3199), together with the excellent and complementary skills of its participants, make this contribution highly worthwhile. G. Metakides Table of contents 1 Perspectives for parallel optical interconnects: introduction . . . . . . . . . . . . . . . . . . . . . . . . . l Pierre Chavel and Philippe lAlanne 1. 1 Optical Interconnects and ESPRIT BRA WOIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1. 2 What are optical interconnects? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. 3 Optical interconnects: how ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. 3. 1 Passive devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. 3. 2 Active devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. 3. 3 Schemes for parallel optical interconnects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. 3. 4 Limits of optical interconnects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1. 4 Optical interconnects: why ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Acknowledgetnents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 First Section: Components Part 1. 1 Passive interconnect components 2 Free space interconnects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Philippe Lalanne and Pierre ChaveZ 2. 1 Introduction: 3D optical interconnects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. 2 Optical free space channels and their implementations . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2. 2. 1 Diffraction and degrees of freedom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2. 2. 2 Two Qasic interconnect setups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Inhalt

1 Perspectives for parallel optical interconnects: introduction.- 1.1 Optical Interconnects and ESPRIT BRA WOIT.- 1.2 What are optical interconnects?.- 1.3 Optical interconnects: how ?.- 1.3.1 Passive devices.- 1.3.2 Active devices.- 1.3.3 Schemes for parallel optical interconnects.- 1.3.4 Limits of optical interconnects.- 1.4 Optical interconnects: why ?.- Acknowledgements.- References.- First Section: Components.- 1.1 Passive interconnect components.- 2 Free space interconnects.- 2.1 Introduction: 3D optical interconnects.- 2.2 Optical free space channels and their implementations.- 2.2.1 Diffraction and degrees of freedom.- 2.2.2 Two basic interconnect setups.- 2.3. Limitations.- 2.3.1 Compactness.- 2.3.2 Alignability.- References.- 3 Reflective and refractive components.- 3.1 Introduction and concept.- 3.1.1 Definition of reflective and refractive components.- 3.1.2 Reflection and refraction for interconnect components.- 3.2 Interconnects with microlens arrays.- 3.2.1 Introduction.- 3.2.2 Interconnection density provided by miniature lenses beyond the paraxial approximation.- 3.2.3 Concluding remarks.- 3.3 Refractive microlens arrays.- 3.3.1 Fields of application.- 3.3.2 Geometry and parameters of microlenses.- 3.3.3 The different fabrication processes.- 3.3.4 Concluding remarks.- References.- 4 Diffractive components: holographic optical elements.- 4.1 Introduction.- 4.2 Types of holographic optical elements.- 4.2.1 Thin holograms.- 4.2.2 Thick holograms.- 4.3 Holographic materials for fixed interconnects.- 4.4 Design of holographic optical elements.- 4.4.1 The hologram phase function.- 4.4.2 Astigmatism and Bragg condition.- 4.4.3 Optimum design for imaging elements.- 4.4.4 Analysis of holographic optical elements.- 4.5 Diffraction efficiency of volume holograms recorded with one or multiple object beams.- 4.5.1 Diffraction efficiency of single volume gratings.- 4.5.2 Simultaneous recording of N object waves.- 4.5.3 Sequential recording of N object waves.- 4.6 Fabrication methods and selected examples.- 4.6.1 Optimized holographic optical elements.- 4.6.2 Sequentially recorded multifacet elements.- 4.6.3 Simultaneously recorded multifacet elements.- 4.6.4 Simultaneous recording of fan-out elements.- 4.6.5 Sequential recording of fan-out elements.- 4.7 Conclusions.- References.- 5 Diffractive components: computer-generated elements.- 5.1 Diffractive optical elements.- 5.2 Design of diffractive optical elements.- 5.2.1 The phase function of diffractive components.- 5.2.2 Optimum design for imaging and beam shaping.- 5.3 Diffraction theory.- 5.3.1 Approximate diffraction theory.- 5.3.2 Rigorous diffraction theory.- 5.3.3 Rigorous modal theory for one-dimensional lamellar gratings.- 5.4 Fabrication technology for diffractive optical elements.- 5.4.1 Primary pattern fabrication.- 5.4.2 Pattern transfer.- 5.4.3 Direct writing of continuous microreliefs.- 5.4.4 Replication techniques.- 5.5 Selected experimental results for DOEs.- 5.5.1 Lenslet arrays.- 5.5.2 Fan-out elements.- 5.6 Future perspectives for diffractive optical elements.- References.- 6 Characterization of Interconnection Components.- 6.1 Introduction.- 6.2 Characterization of the surface structure.- 6.2.1 Macrostructure measurements.- 6.2.2 Microstructure measurements.- 6.3 Characterization of optical performance.- 6.3.1 Wave aberration measurement and related merit functions.- 6.3.2 Calibration problems.- 6.3.3 Direct PSF measurements.- 6.3.4 Angle measurement of reflective/refractive and diffractive deflectors.- 6.3.5 Diffraction efficiency of volume HOE, CGH.- 6.4 Characterization of index profiles.- 6.5 Conclusion.- References.- 1.2 Active interconnect components.- 7 Optoelectronic semiconductor devices.- 7.1 Introduction.- 7.2 Semiconductor materials and growth techniques.- 7.2.1 III-V compound semiconductors.- 7.2.2 Crystal growth techniques.- 7.3 Basic device trends.- 7.3.1 Basic heterostructures.- 7.3.2 Towards lower-dimensional structures.- 7.3.3 Lattice-mismatched heterostructures.- 7.4. Optoelectronic device arrays.- 7.4.1 Introduction.- 7.4.2 Progress in edge-emitting diode lasers.- 7.4.3 Surface-emitting laser arrays.- 7.4.4 Self-electrooptic effect device arrays and vertical-to-surface transmission electrophotonic devices.- 7.5 Summary.- References.- 8 Spatial light modulators for interconnect switches.- 8.1 Introduction.- 8.2 Mechanisms for Spatial Light Modulation.- 8.2.1 Refractive Modulation.- 8.2.2 Absorptive Modulation.-…