, using them as references to determine and discuss the noise floor achieved in this measurement apparatus with a focus on limitations and their tradeoffs. The achieved noise floor in this implementation of a low-cost, all-stock component, low-complexity phase noise analyzer compares favourably to commercial offerings. This setup can find application in particular without a more stable reference or operational quantum system as sensor as would be the case for many component manufacturers.

DOI: 10.48550/arxiv.2310.08258

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arXiv:1603.02137Physical Review AApr 27, 201636 citations

\approx1\ \rm{Hz}

linewidth ultra-stable oscillators near

729\ \rm{nm}

^{40}

^{+}

-ion as a spectrum analyser. We show that the fast phase noise of the laser at relevant Fourier frequencies of 100 kHz to >2 MHz is suppressed to a noise floor of between -110 dBc/Hz and -120 dBc/Hz, an improvement of 20 to 30 dB over state-of-the-art Pound-Drever-Hall-stabilized extended-cavity diode lasers. This strong suppression avoids incoherent (spurious) spin flips during manipulation of optical qubits and improves laser-driven gates in using diode lasers with applications in quantum logic spectroscopy, quantum simulation and quantum computation.