Leiden University Student Repository

Jong, Thijmen de (2026)

Using a microscopic mechanical resonator in a millikelvin environment to probe the CSL model

Master thesis | Physics (MSc)

One of the important questions in modern quantum mechanics is the mechanism behind wavefunction collapse. One possible answer to this problem is formulated in the continuous spontaneous localization model. This model states that quantum systems collapse spontaneously. This spontaneous collapse generates a small amount of energy. We attempt to measure this using a mechanical oscillator which is supercooled in a dry dilution refrigerator with a nuclear demagnetization stage. In this thesis we discuss the results of a measurement run where we reach a cryostat temperature of 3 mk and cantilever Q-factor of approximately 1.4·10^3. Furthermore we test a newly designed detection chip which shows promising results for use in the setup for the CSL experiment. The results of the measurement run do not further constrain the upper bounds of the CSL parameters, but do give us a lot of information on how to improve the setup for future measurements.

CSL

Quantum mechanics

Thermal energy

Author

Jong, Thijmen de

Faculty

Faculty of Science

Specialisation

Physics and business studies

Supervisors

Oosterkamp, T.H.

ECTS Credits

36

Language

en