To test whether a proposed interference experiment with parametric amplifiers to test spontaneous wave function collapse is feasible we measured the spectra of Traveling Wave Parametric Amplifiers ...Show moreTo test whether a proposed interference experiment with parametric amplifiers to test spontaneous wave function collapse is feasible we measured the spectra of Traveling Wave Parametric Amplifiers (TWPAs) and came to the conclusion that that non-tested TWPAs were shorted and had major losses. TWPAs that were measured before also showed major losses. However, we did measure some effects of the expected nonlinear behavior of the Josephson junctions and the creation of idler photons. We have improved a calorimeter and reduced its equilibrium temperatures from 63.2 and 72.1 mK to 40.8 and 44.0 mK by reducing the thermal contact resistances. The calorimeter should be improved further before we can make use of it and measure the dissipation in samples such as the TWPAs. Furthermore, we did simulations on the signal and idler visibilities of the interferometer for a parametric gain up to 13.4 dB and losses in the TWPA up to 6 dB. We found that for large parametric gain the signal and idler visibility converged to a single value dependent of the losses in the TWPA. For all losses we tested, the visibilities were always greater than 0. If a collapse has happened the visibility would be 0. This means that as long as the losses in the TWPA are less than 6 dB and both TWPAs are exactly the same, we can always see from the measured visibilities if a collapse has happened.Show less
