E-raamat: Quantum Well Infrared Photodetectors: Physics and Applications

Introduction		1	(4)
Part I Physics
Basics of Infrared Detection		5	(8)
Blackbody Radiation		5	(2)
Signal, Noise, and Noise-Equivalent Power		7	(3)
Detectivity and Noise-Equivalent Temperature Difference		10	(3)
Semiconductor Quantum Wells and Intersubband Transitions		13	(32)
Quantum Wells		13	(1)
Intersubband Transitions		13	(5)
Intersubband Transition: More Details		18	(11)
Basic Formulae		18	(3)
Calculations for a Symmetric Quantum Well		21	(6)
Transfer-Matrix Method		27	(2)
Corrections to the Intersubband Energy and Lineshape		29	(10)
Coulomb Interaction		29	(2)
Many-Particle Effects		31	(3)
Further Interactions		34	(2)
Band Nonparabolicity		36	(3)
Intersubband Relaxation and Carrier Capture		39	(6)
Electron-Phonon Interaction		40	(1)
Electron-Impurity and Electron-Electron Scattering		41	(4)
Photoconductive QWIP		45	(38)
Dark Current		45	(12)
Simple Models		45	(10)
Self-Consistent and Numerical Models		55	(2)
Photocurrent		57	(8)
Photoconductive Gain		57	(7)
Detector Responsivity		64	(1)
Detector Performance		65	(7)
Detector Noise		65	(2)
Detectivity and Blip Condition		67	(5)
Design of an Optimized Detector		72	(3)
THz QWIPs		75	(8)
Design Considerations		76	(1)
Experimental and Discussion		77	(6)
Photovoltaic QWIP		83	(14)
General Concept		83	(2)
The Four-Zone QWIP		85	(12)
Transport Mechanism and Device Structure		85	(3)
Responsivity and Dark Current		88	(1)
Noise		89	(3)
Detectivity		92	(1)
Time Dependence		93	(1)
Theoretical Performance of Low-Noise QWIPs		94	(3)
Optical Coupling		97	(10)
Simple Experimental Geometries		97	(3)
Gratings for Focal Plane Arrays		100	(4)
Strong Coupling in Waveguides, Polaritons, and Vacuum-Field Rabi Splitting		104	(3)
Miscellaneous Effects		107	(32)
Intersubband Absorption Saturation		107	(2)
Nonlinear Transport and Optical Effects		109	(14)
Extrinsic (Photoconductive) Nonlinearity		109	(6)
Negative Differential Photoconductivity and Electric Field Domains		115	(6)
Intrinsic Nonlinearity		121	(2)
Asymmetry Caused by Dopant Segregation		123	(2)
Coherent Photocurrent		125	(6)
Coherent Control by Optical Fields		125	(3)
Coherent Control Through Potential Offsets		128	(3)
Impact Ionization and Avalanche Multiplication		131	(4)
Radiation Hardness		135	(4)
Related Structures and Devices		139	(36)
High Absorption QWIPs		139	(5)
Absorption Measurements		139	(2)
Detector Characteristics		141	(3)
Multicolor QWIPs		144	(7)
Voltage Switched Multicolor QWIP		146	(3)
Voltage Tuned Multicolor QWIP		149	(2)
Interband and Intersubband Dual-band Detectors		151	(10)
Using the Same Quantum Well		151	(7)
Stacked QWIP and PIN		158	(3)
Integrated QWIP--LED		161	(2)
Quantum Dot Infrared Photodetector		163	(7)
Anticipated Advantages and Current Status		165	(5)
Areas for Improvement		170	(1)
Single Well and Blocked Miniband QWIPs		170	(2)
Transistors and Monolithic Integration		172	(3)
Part II Applications
Thermal Imaging		175	(28)
Signal, Noise, and Noise-Equivalent Temperature Difference		175	(10)
Signal Detection		175	(2)
Detector Noise		177	(1)
System Noise		178	(1)
Thermal Resolution		179	(2)
Fixed-Pattern Noise and NETD of an Array		181	(2)
Modulation Transfer Function		183	(2)
QWIP Cameras		185	(5)
Fabrication of QWIP FPAs		185	(2)
System Integration		187	(1)
Camera Performance		188	(2)
MWIR/LWIR Dual-Band QWIP FPA		190	(6)
Detector Concept		191	(2)
Array Fabrication and FPA Layout		193	(1)
Properties of Dual-Band QWIP Test Devices		194	(1)
System Integration and Dual-Band QWIP FPA Performance		195	(1)
Opportunities for QWIP FPAs in Thermal Imaging		196	(3)
Alternative Architecture and New Functionality of QWIP FPAs		199	(4)
Dynamics, Ultrafast, and Heterodyne		203	(26)
Dynamic Processes in QWIPs		203	(10)
Quantum Well Recharging		204	(4)
Picosecond Photocurrent		208	(5)
High Frequency and Heterodyne QWIPs		213	(7)
Microwave Rectification		213	(3)
Heterodyne Detection		216	(4)
Two-Photon QWIP		220	(9)
Equidistant Three-Level System for Quadratic Detection		220	(3)
Autocorrelation of Subpicosecond Optical Pulses		223	(2)
Externally Switchable Quadratic and Linear Response		225	(4)
Conclusions and outlook		229	(2)
References		231	(16)
Index		247

Harald Schneider completed his PhD at the Max-Planck Institute for Solid State Research (Stuttgart, D) in 1988. In the same year he got the Otto-Hahn-Medal, awarded for the best PhD theses of the Max-Planck-Society. In 1989, he joined the Fraunhofer-Institute for Solid State Physics (Freiburg, D), where he was working on infrared optoelectronics. For the development of infrared cameras of highest thermal resolution, he and his colleagues were awarded the 2001 German Science Foundation Award (Preis des Stifterverbands). In 2005, he switched to the Forschungszentrum Rossendorf, where he is now leading the Semiconductor Spectroscopy Division. He has authored and co-authored more than 150 publications.



H. C. Liu got his PhD in applied physics from the University of Pittsburgh in 1987 as an Andrew Mellon Predoctoral Fellow. He is currently the Quantum Devices Group Leader in the Institute for Microstructural Sciences at the National Research Council of Canada. He has authored and co-authored about 250 refereed journal articles (with about 80 first or sole authored), and given 90 talks (53 invited) at international conferences. He has been elected as a Fellow of the American Physical Society, granted over a dozen patents, and awarded the Herzberg Medal from the Canadian Association of Physicists in 2000 and the Bessel Award from the Alexander von Humboldt Foundation in 2001.



Both authors were involved in QWIPs from the very beginning, including basic research, device optimization, system applications, and novel directions. Their combined work covers a significant share of QWIP research that has been conducted worldwide.