   |
   |
|
|
|
|
|
Info for students |
|
Within the breakdown project there are several possibilities for traineeships for students
SBS pulse compression for sub-nanosecond Stark spectroscopy
Project background: When a plasma is switched on (e.g. fluorescent tube) the state of the neutral gas changes to a charged gas (=plasma). This change from neutral to charged is called plasma breakdown. It is a fundamental process in plasma physics about which very little is known. Also in several applications, e.g. water cleaning and switching on of lamps, plasma breakdown is an important process. The reason for the fact that very little is known about plasma breakdown is that it is a very rapid process, in the order of nanoseconds. To study this effect time-resolved, sub-nanosecond diagnostics have to be used. One of the most important quantities in plasma breakdown is the electric field. The technique that is used in our project to measure electric fields is Stark spectroscopy. This technique uses two tunable, pulsed lasers. The pulse length of these lasers (and accordingly the time resolution) is approximately 5 nsec en not sufficient for our application. To obtain the desired time resolution the laser pulses are compressed by means of Stimulated Brillouin Scattering (SBS) to a length of 300-600 picoseconds.
Student assignment Your assignment is to further develop the SBS pulse compression technique. This involves building an experimental setup, performing measurements for characterization and control of the compressed laser pulses, setting up the hardware for the sub-nanosecond Stark spectroscopy and performing the first sub-nanosecond electric field measurements. You will be working on an experimental setup containng several (Class IV) laser. You will learn to operate this laser system and use it for experiments.
Period: This project is already available and has a length of approximately 10 months.
Interested? For more information, please contact:
Electric field measurements in lamps
Project background: When a fluorescent tube is switched on, it takes a while before light is emitted. During this time, the neutral gas inside the lamp has to be converted into a plasma. This process is called plasma breakdown and very little is known about it. Studying plasma breakdown is complicated by the fact that it is a very rapid process, in the order of nanoseconds. To obtain information on plasma breakdown, active laser techniques are used. An example of such a technique is Stark spectroscopy, which measures electric fields.
Student assignment Your assignment is to investigate the feasibility of doing Stark spectroscopy for electric field measurements in lamps. Especially, focussing the two laser beams into the lamp without damaging the glass of the lamp. You will be working on an experimental setup containng several (Class IV) laser. You will learn to operate this laser system and use it for experiments.
Period: This project is already available and has a length of 2-3 months.
Interested? For more information, please contact:
|
