In collaboration with: Lehrstuhl fuer Nanoelektronik, Technische Universitaet Muenchen (TUM)
The basis idea of the project is to verify the feasibility of an Experimental Method based on laser-stimulated singlet to triplet transition of muonic hydrogen mp atoms to measure the hyperfine splitting in the muonic hydrogen mp ground state level (see aside).
The experimental value of the 3S1 - 1S0 energy difference, if measured with a relative accuracy of 10-4 or better, leads to information on the magnetic structure and the polarizability of the proton, giving complemetary information to experiments on hydrogen (see aside).
A more detailed descritpion of the final experiment is available here. The specification required for the power source according to the above mentioned presentation are reported in the following table
|Power (W/cm2)||10 · 106|
|Linewidth (nm)||< 0.07|
|Pulse duration (ns)||100|
|Tunability precision (nm)||0.007|
In order to explore the feasibility of such a source, it was chosen a laser source, namely a Quantum Cascade Laser (see below on the left), which allows for the tuning of the emission wavelength by mean of engineering the growth pattern (see below on the right). The steps of the project thus have been involved the verification of the achievable power and the tunability of the central wavelength indifferent series of QCL.
The design, realization and testing of the laser sources have been provided by the Technische Universitaet Muenchen, in cooperation with the local Walter Schottky Institut.
The characterization of the lasers, in terms of emitting power, emission wavelenght and tunability as a function of temperature and voltage, have been performed to provide further inputs for the following designs. The idea has been to provide an iterative design-testing procedure to achieve the required performances.
The project ended at the end of 2007. It is now followed by a new project, CNL-muH, aiming to study the optical coupling of the laser emission with the target.