Atom-Based Radio-Frequency Field Calibration and Polarization Measurement Using Cesium nDJ Floquet States

Abstract

We investigate atom-based electric-field calibration and polarization measurement of a 100-MHz linearly polarized radio-frequency (RF) field using cesium Rydberg-atom electromagnetically induced transparency (EIT) in a room-temperature vapor cell. The calibration method is based on matching experimental data with the results of a theoretical Floquet model. The utilized 60DJ fine structure Floquet levels exhibit J-and mj-dependent AC Stark shifts and splittings, and develop even-order RF-modulation sidebands. The Floquet map of cesium 60DJ fine structure states exhibits a series of exact crossings between states of different mj, which are not RF-coupled. These exact level crossings are employed to perform a rapid and precise (±0.5%) calibration of the RF electric field. We also map out three series of narrow avoided crossings between fine structure Floquet levels of equal mj and different J, which are weakly coupled by the RF field via a Raman process. The coupling leads to narrow avoided crossings that can also be applied as spectroscopic markers for RF field calibration. We further find that the line-strength ratio of intersecting Floquet levels with different mj provides a fast and robust measurement of the RF field's polarization.

Измерение напряженности электрического поля СВЧ излучения на частоте радиационного перехода между ридберговскими состояниями атомов -=SUP=-85-=/SUP=-Rb

“…К настоящему времени проведены измерения НЭП в диапазоне от 0.8 до 1000 V/m [3]. По сравнению с существующими, базирующимися на антенной технике, методами квантово-оптический метод измерения НЭП обладает более высокой чувствительностью, ограниченной пределом дробовых шумов фотодетектирования 5 µVcm −1 Hz −1 [4], и высокой точностью с 0.5% неопределенностью измерения величины напряженности поля в несколько десятков V/m [5].…”

Nonlinearity of Microwave Electric Field Coupled Rydberg Electromagnetically Induced Transparency and Autler-Townes Splitting

“…Atoms have also been successfully used for magnetometry due to their sensitivity to magnetic field [6,7]. Rydberg atom, highly excited atom with principal quantum number n > 10, has a large electric polarizability (∝ n 7 ) and a big microwave-transition dipole moments (∝ n 2 ) [8], which make it a good candidate for measuring external electric fields [9][10][11][12][13][14][15]. Rydberg electromagnetically induced transparency (EIT) [16,17], providing a nondestructive detection of Rydberg states, has been investigated in recent years.…”

“…Rydberg electromagnetically induced transparency (EIT) [16,17], providing a nondestructive detection of Rydberg states, has been investigated in recent years. Rydberg EIT can be used to measure a large dynamic range of the electric fields of electromagnetic radiation, including microwave fields [10][11][12], millimeter waves [13], static electric fields [14,15] and subwavelength imaging of microwave electric-field distributions [18,19] and field inhomogeneities [20].…”

Measurement of the Near Field Distribution of a Microwave Horn Using a Resonant Atomic Probe

“…The magnitude of the AT splitting, γ AT , is proportional to Ω MW , and so the magnitude of the splitting can be used to make an atom-based microwave field measurement. Rydberg EIT [10][11][12], a quantum coherence effect of the interaction between Rydberg atoms and lasers, will be employed to optically detect the microwave dressed AT splitting γ AT induced by the microwave field [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. Additionally, we can use this kind of resonant Rydberg transition and fluorescence to detect THz radiation [30,31].…”