Accelerating the development of novel clocks for measuring varying fundamental constants

QSNET++ will accelerate the completion of (i) a clock based on highly-charged ions currently under construction in Birmingham and (ii) a clock based on ultracold molecules being developed at Imperial College. These two clocks will be part of the QSNET network that aims to measure the stability of fundamental constants in order to probe theories of dark matter and other physics beyond the standard model. The clock at Birmingham is based on highly-charged californium ions and is expected to have world-leading sensitivity to the fine-structure constant. To accelerate the development of this clock, we will build a setup for sympathetic cooling of the highly-charged ions. Singly-charged calcium ions will be cooled to low temperature by laser cooling, and they will then cool down the highly-charged ions through their Coulomb interactions. The clock at Imperial College is based on calcium monofluoride molecules trapped in an optical lattice formed by standing waves of laser light. It is expected to have world-leading sensitivity to the proton-to-electron mass ratio. We will develop an ultra-stable laser system to drive the clock transition in these molecules and then use it to study how accurate the clock can be.