Advancements toward Cryogenic System for Electric Gradient Gates and Molecular Qubits*

Dipolar molecular ions possess an expansive state space which offers a unique platform for qubit operations. An application was proposed recently to enable laser free qubit manipulation of molecular ions by applying sub-gigahertz quadrupole RF fields to the electrodes of the ion trap (PhysRevA. 2021, 104, 042605). Addressing the molecular states with this method enables qubit control independent of the ion motional state, in contrast to the optical Lamb-Dicke limit. To provide greater control over the molecular qubit states and suppress unwanted chemical reactions, we have developed a new cryogenic system that is capable of reaching 6K with minimal vibrations. With the aid of this new trap, we are posed to co-trap Ca⁺ with HCl⁺ and pursue non-destructive state readout as a SPAM for molecular quantum computing.