Coherent spin-rotation state transfer in TlF

The aim of CeNTREX (Cold molecule Nuclear Time-Reversal Experiment) is to search for the proton’s electric dipole moment by exploiting the Schiff moment of $^{205}$TlF in the polar molecule thallium fluoride (TlF). To maximize the molecular flux, an electrostatic quadrupole lens is employed to collimate a TlF beam. After rotational cooling, the first few rotational ground states of a cold TlF beam have been emptied into a single J=0 hyperfine level in the $^1\Sigma^+$ electronic ground state. In order to populate a weak-field seeking state that the lens can optimally affect, microwaves are required to transfer TlF from J=0 to J=2. Transitioning from this state preparation region into the electrostatic quadrupole field of the lens will induce non-adiabatic transitions to unwanted states due to rapidly changing fields. This poster describes the recent progress in efficient, coherent spin-rotation state transfer in TlF.