Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

Q: Fachverband Quantenoptik und Photonik

Q 26: Poster – Precision Measurement, Metrology, and Quantum Effects

Q 26.20: Poster

Dienstag, 11. März 2025, 14:00–16:00, Tent

Setup for Laser Excitation of the ²²⁹Th Nucleus in a Cryogenic Environment — •Florian Zacherl¹, Keerthan Subramanian¹, Nutan Kumari Sah¹, Srinivasa Pradeep Arasada¹, Valerii Andriushkov^2,3, Jonas Stricker^1,2, Yumiao Wang^1,4, Ke Zhang¹, Christoph E. Düllmann^1,2,3, Dmitry Budker^1,2,3,5, Thorsten Schumm⁶, Ferdinand Schmidt-Kaler¹, and Lars von der Wense¹ — ¹Johannes Gutenberg University Mainz, Germany — ²Helmholtz Institute Mainz, Germany — ³GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany — ⁴Fudan University, Shanghai, China — ⁵University of California, Berkeley, USA — ⁶Vienna University of Technology, Austria

The low isomeric energy level of only 8.4 eV in ²²⁹Th places the transition wavelength in the vacuum-ultraviolet (VUV) and therefore provides the unique opportunity to excite it with optical lasers. The described setup aims to excite the nucleus of Th⁴⁺ ions in a Th:CaF₂ crystal with a continuous wave (CW) laser around 148 nm. The crystal is placed and excited in a cryogenic environment to reduce vibrations caused by phonons as well as to probe for variations in decay time at very low temperatures. Entering the cryogenic regime will also provide the possibility of better investigation of temperature dependent transition frequency shifts. The main part of the detection system of the radiative decay including a photomultiplier tube (PMT) is decoupled from the cryogenic area and placed in a separate chamber.

This work is supported by the BMBF Quantum Futur II Grant Project ’NuQuant’ (FKZ 13N16295A).

Keywords: Th-229; Thorium; Nuclear Clock; Crystal; Cryogenic