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DAZZLERTM System Manual Part I : Installation & Operation V3.00

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DAZZLERTM System Manual Part I : Installation & Operation V3.00 DAZZLERTM system manual Part I : installation & operation V3.00 - 8th April 2019 i i/94 Contents 1 Introduction2 1.1 System components..................................2 1.1.1 Crystal unit..................................2 1.1.2 RF generator.................................3 1.1.3 Laptop computer and software........................4 2 Physics 6 2.1 AOPDF principle...................................6 2.1.1 Phase-matching conditions..........................6 2.1.2 Poynting vectors...............................7 2.1.3 Pulse-shaping mechanism..........................8 2.2 Key parameters.................................... 10 2.2.1 Diffraction efficiency............................. 10 2.2.2 Spectral resolution.............................. 11 2.2.3 Number of independent programming points................ 11 2.2.4 Input beam angular aperture (divergence)................. 11 2.2.5 Acoustic power density to drive n points.................. 11 2.2.6 Convolution with an acoustical linear chirp................. 12 2.2.7 Maximal pulse shaping capability...................... 12 2.2.8 Crystal dispersion compensation....................... 12 2.2.9 Beam orientations............................... 13 2.3 Formulæ........................................ 13 3 Installation & setup 15 3.1 Connections...................................... 15 3.1.1 Connecting the unit and starting the software............... 15 3.1.2 Define the general settings.......................... 16 3.1.3 Define the waveform combination options.................. 16 3.1.4 Define the spectral amplitude........................ 16 3.1.5 Define the spectral phase........................... 17 3.1.6 Launching a waveform............................ 17 3.1.7 Stopping the Program............................ 17 3.2 Examples of experimental setup........................... 17 3.2.1 Ultrafast CPA laser controlled by a Dazzler................ 18 3.2.2 Dazzler after an optical parametric amplifier................ 18 ii DAZZLERTM system manual Part I : installation & operation CONTENTS 3.3 Optical Alignment.................................. 18 3.3.1 Frequency Calibration............................ 20 3.3.2 Dazzler operating at the output of a seed oscillator............ 21 3.3.3 Measurement of the Dazzler diffraction efficiency:............. 21 3.3.4 Dazzler operating in other setups...................... 22 4 Triggering 24 4.1 Triggering issues in the DazzlerTM .......................... 24 4.1.1 Wiring and signal level............................ 24 4.1.2 Optimum trigger settings........................... 24 4.1.3 Effects of incorrect trigger settings..................... 26 4.2 The Trig&Mode panel................................ 26 4.2.1 Panel presentation.............................. 28 4.2.2 Key parameters................................ 29 4.2.3 Trigger to Laser adjustment procedure................... 30 4.3 Modes of operation.................................. 31 4.3.1 Normal mode................................. 31 4.3.2 Trig on Previous mode............................ 32 4.3.3 Influence of Trigger Delay limits....................... 32 4.3.4 No Delay................................... 33 4.3.5 High repetition rate.............................. 34 5 Software & Operation 36 5.1 Front panel...................................... 36 5.1.1 Blue area: power, constant gain, zero, load wave in memory....... 37 5.1.2 Orange area: spectral amplitude control.................. 38 5.1.3 Green Area: spectral phase control..................... 38 5.1.4 Grey Area : Waveform Combination.................... 39 5.1.5 Graphs..................................... 39 5.1.6 Loaded waves................................. 40 5.1.7 Machine controls............................... 41 5.1.8 Damage prevention.............................. 42 5.2 Menu bar....................................... 44 5.2.1 File Menu................................... 44 5.2.2 Setup menu.................................. 44 5.2.3 Monitor Menu................................. 45 5.2.4 Monitor configuration............................ 45 5.2.5 Monitor maintenance............................. 45 5.3 Files, paths and file formats............................. 47 5.3.1 Default directory............................... 47 5.3.2 Data Files................................... 48 5.3.3 C:ndazzler................................... 48 5.4 Wave files....................................... 48 5.4.1 amp.txt and phase.txt file format...................... 49 5.5 Parameters...................................... 50 5.5.1 Parameter files................................ 50 5.5.2 Location of parameters files......................... 52 V3.00 - 8th April 2019 iii iii/94 DAZZLERTM system manual Part I : installation & operation CONTENTS 5.6 Alarms operation................................... 53 5.6.1 Alarms description.............................. 54 5.7 Warnings....................................... 58 5.7.1 Missed triggers due to timing........................ 58 5.7.2 Missed triggers due to power......................... 58 5.7.3 Missed triggers unreported.......................... 58 5.8 Troubleshooting.................................... 59 5.8.1 Missing parameters.............................. 59 5.8.2 E-mail reports................................. 59 5.8.3 Screen captures................................ 60 6 Remote control 61 6.1 Remote control generalities.............................. 61 6.1.1 Client-Server models............................. 61 6.1.2 Documentation................................ 62 6.2 Basic text remote control............................... 62 6.2.1 Requests.................................... 62 6.2.2 Atomic write................................. 63 6.2.3 Error handling................................ 64 6.2.4 File C:/dazzler/paths.txt.......................... 64 6.2.5 Star commands................................ 64 6.2.6 Wave file inclusion in request (#wave)................... 66 6.3 Dazzler Network Remote Toolkit.......................... 67 6.3.1 Scope and Principle.............................. 67 6.3.2 Walk through of a simple code........................ 67 7 Cabling tips 70 7.1 Basic principles.................................... 70 7.1.1 Ground plane, layout & crossings...................... 70 7.1.2 Use of EMI ferrites.............................. 71 7.1.3 Termination of signals............................ 71 7.2 USB cable....................................... 71 7.3 Practical examples.................................. 73 8 RF Generator description 78 8.1 Overview........................................ 78 8.2 Indicators....................................... 78 8.2.1 Power indicator................................ 79 8.2.2 L1 indicator.................................. 79 8.2.3 L2 indicator.................................. 79 8.2.4 Trigger indicator............................... 79 8.2.5 AUX indicator................................ 79 8.2.6 RF ON indicator............................... 79 8.3 Logic levels & signals................................. 80 8.4 Input signals...................................... 80 8.4.1 Input signal trigger ............................ 80 8.4.2 Input signal aux ............................... 80 V3.00 - 8th April 2019 iv iv/94 DAZZLERTM system manual Part I : installation & operation CONTENTS 8.4.3 ExtClock................................... 80 8.5 Output signal RF out................................. 81 8.6 RF cycles description................................. 81 8.6.1 Single cycles.................................. 81 8.6.2 Continuous mode............................... 84 8.6.3 Alternate mode................................ 84 8.7 Output signals S1-S4................................. 86 8.7.1 Output signal S1............................... 86 8.7.2 Output signal S2............................... 86 8.7.3 Output signal list............................... 87 8.7.4 Descriptions of selectable signals...................... 87 8.8 Specifications..................................... 92 Bibliography 92 V3.00 - 8th April 2019 v v/94 List of Figures 1.1 Simplified schematic of the RF generator......................3 1.2 DazzlerTM software front panel............................4 2.1 Phase-matching conditions and Poynting vector directions............7 2.2 Explanation of the Dazzler principle in terms of group delay control.......8 2.3 Diffracted and transmitted beams orientation for DazzlerTMHR model...... 13 3.1 Setup of an Ultrafast CPA Laser with a Dazzler.................. 18 3.2 Setup of an OPA with a Dazzler........................... 19 3.3 Dazzler crystal installation.............................. 19 3.4 Details of the Dazzler crystal............................ 20 3.5 Beam position on the input face........................... 20 3.6 Example of spectrum with hole........................... 20 3.7 Short Acoustic Pulse and Typical Oscilloscope Measure.............. 22 3.8 Chirped Pulse used to adjust the x and y position................. 23 4.1 Optimum trigger settings............................. 25 4.2 Left: acoustic wave position in the crystal when the optical wave propagates through the crystal (acoustic wave unclipped), Right: Equivalent spectrum and time graphs...................................... 26 4.3 Incorrect trigger settings: Trigger Delay too short............... 26 4.4 Incorrect trigger settings: Trigger Delay too long................ 27 4.5 Trigger Delay too short: Left: acoustic wave position in the crystal when the optical pulse is in the crystal Right: Equivalent spectrum
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