A Swiss quantum-logic clock made of a single molecule
Kaveh Najafian, Ziv Meir, Gregor Hegi, Mudit Sinhal, Stefan Willitsch
Department of Physical Chemistry, University of Basel, Switzerland
The application of quantum-logic techniques[1] to the spectroscopy of trapped atomic ions has enabled the determination of atomic properties at unprecedented levels of precision[2]. These advancement have lead to the creation of the most precise man-made measurement devices, optical atomic clocks, with fractional accuracy and precision on the level of 10-18 [3,4]. Up-to-now, atomic-clocks implementations were limited to microwave and optical transitions in atoms and ions.
We propose to use THz molecular vibrational transitions to create a new mid-IR molecular clock. The additional rotational and vibrational degrees of freedom in our chosen molecule, N2+, are highly suitable for clock operation and precision-spectroscopic tests of fundamental theories such as time variation of fundamental constants[5, 6]. We are currently establishing a complete toolbox for high-precision spectroscopy of single molecules using quantum-logic methods, their initialization, coherent manipulation and non-destructive interrogation by coupling them to a co-trapped single atomic ion.
[1] H. Häffner et al., Physics Reports 469 (2008), 155.
[2] P. O. Schmidt et al., Science 309 (2005), 749.
[3] S. L. Campbell et al., Science 358 (2017), 90.
[4] N. Huntemann et al., Phys. Rev. Lett. 116 (2016), 063001.
[5] M. Kajita et al., Phys. Rev. A 89 (2014), 032509.
[6] M. Germann et al., Nature Physics 10 (2014), 820.