Contents 2 Pulsed Optics C.Hirlimann... 2.1 Introduction 4444444 25 2.2 Linear Optics 26 2.2.1 Light....... 26 2.2.2 Light Pulses...…………… 28 2.2.3 Relationship Between Duration and Spectral Width.......... 30 2.2.4 Propagation of a Light Pulse in a Transparent Medium....... 32 2.3 Nonlinear Optics.................................. 38 2.3.1 Second-Order Susceptibility............................... 38 2.3.2 Third-Order Susceptibility......... 45 2.4 Cascaded Nonlinearities......................... 444 53 2.5 Problems....… 55 Further Reading...·· 56 56 nCes........。。。。。。。。。.........::::::::。。。。。。 3 Methods for the Generation of Ultrashort Laser Pulses: Mode-Locking A.Ducasse,C.Rulliere and B.Couillaud........................... 57 3.1 Introduction ................................................ 57 3.2 Principle of the Mode-Locked Operating Regime 60 3.3 General Considerations Concerning Mode-Locking................ 66 3.4 The Active Mode-Locking Method........ 67 3.5 Passive and Hybrid Mode-Locking Methods...................... 74 3.6 Self-Locking of the Modes .................................... 81 References.. 87 4 Further Methods for the Generation of Ultrashort Optical Pulses C.Hirlimann..……… 89 41 ntroduction.… 89 4.1.1 Time-Frequency Fourier Relationship 89 4.2 Gas Lasers......…… 91 421Mode-L0 cking… 92 4.2.2 Pulse Compression....................................... 92 4.3 Dye Lasers .............. 94 4.3.1 Synchronously Pumped Dye Lasers.......··· 94 4.3.2 Passive Mode-Locking..... 96 4.3.3 Really Short Pulses ....... ...101 4.3.4 Hybrid Mode-Locking...... ...102 4.8.5 Wavelength Tuning......................................104 4.4 Solid-State Lasers ................................. .....106 4.4.1 The Neodymium1on..........................106 4.4.2 The Titanium Ion ..................................... .107 4.4.3F-Centers....................109
x Contents 2 Pulsed Optics C. Hirlimann .................................................... 25 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2.2 Linear Optics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2.2.1 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2.2.2 Light Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2.2.3 Relationship Between Duration and Spectral Width . . . . . . . . . . 30 2.2.4 Propagation of a Light Pulse in a Transparent Medium . . . . . . . 32 2.3 Nonlinear Optics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 2.3.1 Second-Order Susceptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 2.3.2 Third-Order Susceptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 2.4 Cascaded Nonlinearities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 2.5 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 3 Methods for the Generation of Ultrashort Laser Pulses: Mode-Locking A. Ducasse, C. Rulli`ere and B. Couillaud ........................... 57 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 3.2 Principle of the Mode-Locked Operating Regime . . . . . . . . . . . . . . . . . 60 3.3 General Considerations Concerning Mode-Locking . . . . . . . . . . . . . . . . 66 3.4 The Active Mode-Locking Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 3.5 Passive and Hybrid Mode-Locking Methods. . . . . . . . . . . . . . . . . . . . . . 74 3.6 Self-Locking of the Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 4 Further Methods for the Generation of Ultrashort Optical Pulses C. Hirlimann .................................................... 89 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 4.1.1 Time–Frequency Fourier Relationship . . . . . . . . . . . . . . . . . . . . . . 89 4.2 Gas Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 4.2.1 Mode-Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 4.2.2 Pulse Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 4.3 Dye Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 4.3.1 Synchronously Pumped Dye Lasers . . . . . . . . . . . . . . . . . . . . . . . . 94 4.3.2 Passive Mode-Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 4.3.3 Really Short Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 4.3.4 Hybrid Mode-Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 4.3.5 Wavelength Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 4.4 Solid-State Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 4.4.1 The Neodymium Ion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 4.4.2 The Titanium Ion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 4.4.3 F-Centers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Contents xi 4.4.4 Soliton Laser.................... .......109 4.5 Pulse Generation Without Mode-Locking.... ….111 4.5.1 Distributed Feedback Dye Laser (DFDL)...................111 4.5.2 Traveling-Wave Excitation......... ...112 4.5.3 Space-Time Selection ......................... ....112 4.5.4 Quenched Cavity........................................113 4.6 New Developments.....................114 4.6.1 Diode Pumped Lasers....................................114 4.6.2 Femtosecond Fibber Lasers...............................114 4.6.3 Femtosecond Diode Lasers .....115 4.6.4 New Gain Materials............... ..117 4.7 Trends ................... .118 References..。.… ..119 5 Pulsed Semiconductor Lasers T.Amand and X.Marie................... ...125 5.1 Introduction.................................................125 5.2 Semiconductor Lasers:Principle of Operation....................126 5.2.1 Semiconductor Physics Background........................126 5.2.2 pn Junction -Homojunction Laser ........................129 5.3 Semiconductor Laser Devices......................... .....131 5.3.1 Double-Heterostructure Laser .................. .....132 5.3.2 Quantum Well Lasers......................... ..137 5.3.3 Strained Quantum Well and Vertical-Cavity Surface-Emitting Lasers...................................................139 5.4 Semiconductor Lasers in Pulsed-Mode Operation.................141 5.4.1 Gain-Switched Operation.................................143 5.4.2 Q-Switched Operation....................................150 5.4.3 Mode-Locked Operation... ….159 5.4.4 Mode-Locking by Gain Modulation ........................160 5.4.5 Mode-Locking by Loss Modulation:Passive Mode-Locking by Absorption Saturation...................................163 5.4.6 Prospects for Further Developments........................170 References......................................................172 6 How to Manipulate and Change the Characteristics of Laser Pulses f.Saln..............................................175 6.1 Introduction........... ...175 6.2 Pulse Compression.....·..· .175 6.3Amplification................................................178 6.4 Wavelength Tunability ........................................185 6.4.1 Second-and Third-Harmonic Generation.......... ...186 6.4.2 Optical Parametric Generators (OPGs)and Amplifiers (OPAs)187 6.5 Conclusion..........192
Contents xi 4.4.4 Soliton Laser. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 4.5 Pulse Generation Without Mode-Locking . . . . . . . . . . . . . . . . . . . . . . . . 111 4.5.1 Distributed Feedback Dye Laser (DFDL) . . . . . . . . . . . . . . . . . . . 111 4.5.2 Traveling-Wave Excitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 4.5.3 Space–Time Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 4.5.4 Quenched Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 4.6 New Developments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 4.6.1 Diode Pumped Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 4.6.2 Femtosecond Fibber Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 4.6.3 Femtosecond Diode Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 4.6.4 New Gain Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 4.7 Trends . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 5 Pulsed Semiconductor Lasers T. Amand and X. Marie .......................................... 125 5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 5.2 Semiconductor Lasers: Principle of Operation . . . . . . . . . . . . . . . . . . . . 126 5.2.1 Semiconductor Physics Background . . . . . . . . . . . . . . . . . . . . . . . . 126 5.2.2 pn Junction – Homojunction Laser . . . . . . . . . . . . . . . . . . . . . . . . 129 5.3 Semiconductor Laser Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 5.3.1 Double-Heterostructure Laser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 5.3.2 Quantum Well Lasers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 5.3.3 Strained Quantum Well and Vertical-Cavity Surface-Emitting Lasers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 5.4 Semiconductor Lasers in Pulsed-Mode Operation . . . . . . . . . . . . . . . . . 141 5.4.1 Gain-Switched Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 5.4.2 Q-Switched Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 5.4.3 Mode-Locked Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 5.4.4 Mode-Locking by Gain Modulation . . . . . . . . . . . . . . . . . . . . . . . . 160 5.4.5 Mode-Locking by Loss Modulation: Passive Mode-Locking by Absorption Saturation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 5.4.6 Prospects for Further Developments. . . . . . . . . . . . . . . . . . . . . . . . 170 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172 6 How to Manipulate and Change the Characteristics of Laser Pulses F. Salin ........................................................ 175 6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 6.2 Pulse Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 6.3 Amplification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 6.4 Wavelength Tunability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 6.4.1 Second- and Third-Harmonic Generation . . . . . . . . . . . . . . . . . . . 186 6.4.2 Optical Parametric Generators (OPGs) and Amplifiers (OPAs) 187 6.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
xii Contents 6.6 Problems..............192 eference8................................................l93 7 How to Measure the Characteristics of Laser Pulses L.Sarger and J.Oberle...........................................195 7.1 Introduction...........................195 7.2 Energy Measurements.........................................196 7.3 Power Measurements .........................................197 7.4 Measurement of the Pulse Temporal Profile............. .198 7.4.1 Pure Electronic Methods.................................198 7.4.2All-0 ptical Methods..................202 7.5 Spectral Measurements........................................215 7.6 Amplitude-Phase Measurements...............................216 7.6.1 FROG Technique............................... .217 7.6.2 Frequency Gating .218 7.6.3 Spectal Interferometry and SPIDER........ .219 References ........................................ .221 8 Spectroscopic Methods for Analysis of Sample Dynamics C.Rulliere,T.Amand and X.Marie...............................223 8.1 Introduction.................................................223 8.2 "Pump-Probe"Methods......................................224 8.2.1 General Principles......................224 8.2.2 Time-Resolved Absorption in the UV-Visible Spectral Domain 225 8.2.3 Time-Resolved Absorption in the IR Spectral Domain ..233 8.2.4 Pump-Probe Induced Fluorescence........................235 8.2.5 Probe-Induced Raman Scattering..........................237 8.2.6 Coherent Anti-Stokes Raman Scattering (CARS) …….241 8.3 Time-Resolved Emission Spectroscopy:Electronic Methods........249 8.3.1 Broad-Bandwidth Photodetectors..........................250 8.3.2 The Streak Camera......................................250 8.3.3 "Single"-Photon Counting................................250 8.4 Time-Resolved Emission Spectroscopy:Optical Methods...........252 8.4.1 The Kerr Shutter........................................252 8.4.2 Up-conversion Method 。。。。。 8.5 Time-Resolved Spectroscopy by Excitation Correlation............260 8.5.1 Experimental Setup......................................261 8.5.2 Interpretation of the Correlation Signal.....................262 8.5.3 Example of Application......................... ....263 8.6 Transient-Grating Techniques........................ ......264 8.6.1 Principle of the Method:Degenerate Four-Wave Mixing (DFWM)........... ……….264 8.6.2 Example of Application:t-Stilbene Molecule ................266 8.6.3 Experimental Tricks.....................................269 8.7 Studies Using the Kerr Effect ..................................270
xii Contents 6.6 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 7 How to Measure the Characteristics of Laser Pulses L. Sarger and J. Oberl´e ........................................... 195 7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 7.2 Energy Measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 7.3 Power Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 7.4 Measurement of the Pulse Temporal Profile . . . . . . . . . . . . . . . . . . . . . . 198 7.4.1 Pure Electronic Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 7.4.2 All-Optical Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202 7.5 Spectral Measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 7.6 Amplitude–Phase Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 7.6.1 FROG Technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217 7.6.2 Frequency Gating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218 7.6.3 Spectal Interferometry and SPIDER . . . . . . . . . . . . . . . . . . . . . . . 219 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 8 Spectroscopic Methods for Analysis of Sample Dynamics C. Rulli`ere, T. Amand and X. Marie ............................... 223 8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 8.2 “Pump–Probe” Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 8.2.1 General Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 8.2.2 Time-Resolved Absorption in the UV–Visible Spectral Domain 225 8.2.3 Time-Resolved Absorption in the IR Spectral Domain . . . . . . . . 233 8.2.4 Pump–Probe Induced Fluorescence . . . . . . . . . . . . . . . . . . . . . . . . 235 8.2.5 Probe-Induced Raman Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . 237 8.2.6 Coherent Anti-Stokes Raman Scattering (CARS) . . . . . . . . . . . . 241 8.3 Time-Resolved Emission Spectroscopy: Electronic Methods . . . . . . . . 249 8.3.1 Broad-Bandwidth Photodetectors. . . . . . . . . . . . . . . . . . . . . . . . . . 250 8.3.2 The Streak Camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 8.3.3 “Single”-Photon Counting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 8.4 Time-Resolved Emission Spectroscopy: Optical Methods. . . . . . . . . . . 252 8.4.1 The Kerr Shutter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252 8.4.2 Up-conversion Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255 8.5 Time-Resolved Spectroscopy by Excitation Correlation . . . . . . . . . . . . 260 8.5.1 Experimental Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 8.5.2 Interpretation of the Correlation Signal . . . . . . . . . . . . . . . . . . . . . 262 8.5.3 Example of Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 8.6 Transient-Grating Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 8.6.1 Principle of the Method: Degenerate Four-Wave Mixing (DFWM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 8.6.2 Example of Application: t-Stilbene Molecule . . . . . . . . . . . . . . . . 266 8.6.3 Experimental Tricks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269 8.7 Studies Using the Kerr Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Contents xiji 8.7.1 Kerr "Ellipsometry".....................................270 8.8 Laboratory Demonstrations....................................273 8.8.1 How to Demonstrate Pump-Probe Experiments Directly.....273 8.8.2 How to Observe Generation of a CARS Signal by Eye........276 8.8.3 How to Build a Kerr Shutter Easily for Demonstration.......278 8.8.4 How to Observe a DFWM Diffraction Pattern Directly.......279 References..............................280 9 Coherent Effects in Femtosecond Spectroscopy:A Simple Picture Using the Bloch Equation M.Joffre.......................................................283 91 ntroduction.....................283 9.2 Theoretical Model......………… .283 9.2.1 Equation of Evolution....................................284 9.2.2 Perturbation Theory .....286 9.2.3 Two-Level Model....... ...289 9.2.4 Induced Polarization .....................................290 9.3 Applications to Femtosecond Spectroscopy.......................291 9.3.1 First Order ................... .291 9.3.2 Second Order ................. ….292 9.3.3 Third Order ..296 9.4 Multidimensional Spectroscopy........... ...304 9.5 Conclusion…… .306 9.6 Problems........................................ ··..306 References。。 ...307 10 Terahertz Femtosecond Pulses A.Bonvalet and M.Joffre ........................................309 10.1 Introduction................................................309 10.2 Generation of Terahertz Pulses................................310 10.2.1 Photoconductive Switching.............................311 10.2.2 Optical Rectification in a Nonlinear Medium..............314 10.3 Measurement of Terahertz Pulses..............................316 10.3.1 Fourier Transform Spectroscopy.........................316 10.3.2 Photoconductive Sampling..............................319 10.3.3 Free-Space Electro-Optic Sampling ..319 10.4 Some Experimental Results...................................321 10.5 Time-Domain Terahertz Spectroscopy..........................325 10.6 Conclusion.............. ....326 10.7 Problems ......... ..329 References...·.·······… .330
Contents xiii 8.7.1 Kerr “Ellipsometry” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 8.8 Laboratory Demonstrations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 8.8.1 How to Demonstrate Pump–Probe Experiments Directly . . . . . 273 8.8.2 How to Observe Generation of a CARS Signal by Eye . . . . . . . . 276 8.8.3 How to Build a Kerr Shutter Easily for Demonstration . . . . . . . 278 8.8.4 How to Observe a DFWM Diffraction Pattern Directly . . . . . . . 279 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280 9 Coherent Effects in Femtosecond Spectroscopy: A Simple Picture Using the Bloch Equation M. Joffre ....................................................... 283 9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 9.2 Theoretical Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 9.2.1 Equation of Evolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284 9.2.2 Perturbation Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 9.2.3 Two-Level Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289 9.2.4 Induced Polarization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 9.3 Applications to Femtosecond Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . 291 9.3.1 First Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291 9.3.2 Second Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292 9.3.3 Third Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296 9.4 Multidimensional Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304 9.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306 9.6 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 10 Terahertz Femtosecond Pulses A. Bonvalet and M. Joffre ........................................ 309 10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309 10.2 Generation of Terahertz Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310 10.2.1 Photoconductive Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311 10.2.2 Optical Rectification in a Nonlinear Medium . . . . . . . . . . . . . . 314 10.3 Measurement of Terahertz Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 316 10.3.1 Fourier Transform Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . 316 10.3.2 Photoconductive Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319 10.3.3 Free-Space Electro-Optic Sampling . . . . . . . . . . . . . . . . . . . . . . 319 10.4 Some Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321 10.5 Time-Domain Terahertz Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . 325 10.6 Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326 10.7 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
xiv Contents 11 Coherent Control in Atoms,Molecules and Solids T.Amand,V.Blanchet,B.Girard and X.Marie....................333 1l.1 ntroduction...............333 11.2 Coherent Control in the Frequency Domain........... .....334 11.3 Temporal Coherent Control......................... .....339 11.3.1 Principles of Temporal Coherent Control.................339 11.3.2 Temporal Coherent Control in Solid State Physics.........347 11.4 Coherent Control with Shaped Laser Pulses.....................356 11.4.1 Generation of Chirped or Shaped Laser Pulses .357 11.4.2 Coherent Control with Chirped Laser Pulses..............360 11.4.3 Coherent Control with Shaped Laser Pulses...............365 11.5 Coherent Control in Strong Field....................... .374 11.6 Conclusic0n......… .385 References.......··· ..387 12 Attosecond Pulses E.Constant and E.Mevel............................. ··.395 12.1 Introduction...................…… ··....395 12.2 High-Order Harmonic Generation:A Coherent,Short-Pulse XUV Source................................................396 12.3 Semiclassical Picture of HHG.................................398 12.3.1 Atomic Ionization in the Tunnel Domain .....399 12.3.2 Electronic Motion in an Electric Field....................400 12.3.3 Semiclassical View of HHG.............................402 12.4 High-Order Harmonic Generation as an Attosecond PulseSource................................................405 12.4.1 Emission of an Isolated Attosecond Pulse.................408 12.5 Techniques for Measurement of Attosecond Pulses...............412 12.5.1 Cross Correlation......................................412 12.5.2 Laser Streaking.................414 12.5.3 Autocorrelation.................415 12.5.4 XUV-induced Nonlinear Processes ............. ..416 12.5.5 Splitting,Delay Control and Recombination of Attosecond Pulses.....................................416 12.6 Applications of Attosecond Pulses .............................417 12.7Conclusion..................................................419 References..............419 Index.。 …….423
xiv Contents 11 Coherent Control in Atoms, Molecules and Solids T. Amand, V. Blanchet, B. Girard and X. Marie .................... 333 11.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333 11.2 Coherent Control in the Frequency Domain . . . . . . . . . . . . . . . . . . . . . 334 11.3 Temporal Coherent Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339 11.3.1 Principles of Temporal Coherent Control . . . . . . . . . . . . . . . . . 339 11.3.2 Temporal Coherent Control in Solid State Physics . . . . . . . . . 347 11.4 Coherent Control with Shaped Laser Pulses . . . . . . . . . . . . . . . . . . . . . 356 11.4.1 Generation of Chirped or Shaped Laser Pulses . . . . . . . . . . . . 357 11.4.2 Coherent Control with Chirped Laser Pulses . . . . . . . . . . . . . . 360 11.4.3 Coherent Control with Shaped Laser Pulses . . . . . . . . . . . . . . . 365 11.5 Coherent Control in Strong Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374 11.6 Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 387 12 Attosecond Pulses E. Constant and E. M´evel ......................................... 395 12.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395 12.2 High-Order Harmonic Generation: A Coherent, Short-Pulse XUV Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396 12.3 Semiclassical Picture of HHG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398 12.3.1 Atomic Ionization in the Tunnel Domain . . . . . . . . . . . . . . . . . 399 12.3.2 Electronic Motion in an Electric Field . . . . . . . . . . . . . . . . . . . . 400 12.3.3 Semiclassical View of HHG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402 12.4 High-Order Harmonic Generation as an Attosecond Pulse Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405 12.4.1 Emission of an Isolated Attosecond Pulse . . . . . . . . . . . . . . . . . 408 12.5 Techniques for Measurement of Attosecond Pulses . . . . . . . . . . . . . . . 412 12.5.1 Cross Correlation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412 12.5.2 Laser Streaking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 414 12.5.3 Autocorrelation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415 12.5.4 XUV-induced Nonlinear Processes . . . . . . . . . . . . . . . . . . . . . . . 416 12.5.5 Splitting, Delay Control and Recombination of Attosecond Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416 12.6 Applications of Attosecond Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417 12.7 Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419 Index .......................................................... 423