Paper: Analysis of an Integer-N Frequency Synthesizer for Trapped Ion Quantum Computers
Marvin Jaeger · Simon Schulz · Alexander Keolpin
IEEE · 2026
Qubit implementations like trapped ions can be controlled by microwave signals in the gigahertz range, which require a local oscillator (LO) for upconversion. The LO superimposes a static frequency offset and phase noise, both leading to errors in qubit gate operation. Both error terms can be reduced by implementing the LO as an integer-N frequency synthesizer, where a phase-locked loop controls and stabilizes the frequency. An exemplary integer-N frequency synthesizer is realized and its performance for quantum computers is characterized in this work. The qubit fidelity calculated based on phase noise measurement results is above 99.943% for primitive π-gates. Keywords — Fidelity, integer-N synthesizer, local oscillator (LO), phase noise, quantum computer, synthesizer, trapped ion.
