Detecting Axial Ratio of Microwave Field with High Resolution Using NV Centers in Diamond

Abstract

Polarization property characterization of the microwave (MW) field with high speed and resolution is vitally beneficial as the circularly-polarized MW field plays an important role in the development of quantum technologies and satellite communication technologies. In this work, we propose a scheme to detect the axial ratio of the MW field with optical diffraction limit resolution with a nitrogen vacancy (NV) center in diamond. Firstly, the idea of polarization selective detection of the MW magnetic field is carried out using a single NV center implanted in a type-IIa CVD diamond with a confocal microscope system achieving a sensitivity of 1.7 μT/Hz. Then, high speed wide-field characterization of the MW magnetic field at the submillimeter scale is realized by combining wide-field microscopy and ensemble NV centers inherent in a general CVD diamond. The precision axial ratio can be detected by measuring the magnitudes of two counter-rotating circularly-polarized MW magnetic fields. The wide-field detection of the axial ratio and strength parameters of microwave fields enables high speed testing of small-scale microwave devices.

Measurements of Spatial Angles Using Diamond Nitrogen–Vacancy Center Optical Detection Magnetic Resonance

“…The diamond NV center is a nanomaterial with combined optical and magnetic resonance capabilities, holding broad application potential in quantum information and biomedical fields [ 16 , 17 , 18 ]. The optical detection magnetic resonance (ODMR) technology primarily exploits the characteristics of a diamond NV center by laser exciting the NV center to specific energy levels, manipulating the spin state of the NV center through microwave radiation, and finally obtaining information on the magnetic field intensity of the sample by detecting changes in its fluorescence intensity [ 19 , 20 ]. The magnetic field is a fundamental physical property of various substances.…”