Kihwan Kim Yisoo Na Jungbae Yoon Dongkwon Lee Hee Seong Kang Chul-Ho Lee Chulki Kim Donghun Lee 2025-06-05T08:30:34Z 2025-06-05T08:30:34Z 2025-06-04 2025-06 https://pubs.kist.re.kr/handle/201004/152584 We experimentally demonstrate a protocol that effectively suppresses low-frequency noise, including the qubit-bath interaction in diamond. This enables the detection of ac signals below 1 MHz with an increased signal-to-noise ratio of up to approximately 17. The method is based on ac magnetometry with single- and doubly dressed states, which are adiabatically transferred from the initial bare qubit states via concatenated continuous dynamical decoupling. We compare the dressed-state protocols with a conventional pulsed dynamical decoupling method, XY16. This work paves an alternative way toward the sensitive detection of weakly coupled nuclear spins in low-field NMR experiments and submegahertz ac magnetometry. English American Physical Society Suppression of spin-bath and low-frequency noise for submegahertz ac magnetometry based on a doubly dressed spin qubit in diamond Article 10.1103/PhysRevApplied.23.064004 1 Physical Review Applied, v.23, no.6 Physical Review Applied 23 6 N scie scopus 001512845100002 Physics, Applied Physics Article NUCLEAR-MAGNETIC-RESONANCE PYTHON FRAMEWORK SPECTROSCOPY POLARIZATION DYNAMICS QUTIP