Related papers: Cavity-enhanced Ramsey spectroscopy at a Rydberg-a…
Rydberg atoms have great potential in electric field measurement and have an advantage with a large frequency bandwidth from the kHz to the THz scale. However, the sensitivity for measuring a weak MHz electric field signal is limited by the…
Ensembles of atoms interacting via their Rydberg levels, known as "superatoms" for their ability to encode qubits and to emit single photons, attract increasing attention as building blocks for quantum network nodes. Assessing their…
We experimentally demonstrate the resonance fluorescence of a two-level artificial atom strongly coupled to a single-mode cavity field. The effect was theoretically predicted thirty years ago by Savage [Phys. Rev. Lett. 63, 1376 (1989)].…
Rydberg atoms in a gas form are highly sensitive electric field probes capable of detecting and measuring the amplitude, phase, and polarization of broadband time-varying signals. Here, we present the performance of a frequency modulated…
The dissociation dynamics of the $\tilde{A}$-state of ammonia have been studied using a resonant multiphoton ionisation probe in a photoelectron spectroscopy experiment. The use of a resonant intermediate in the multiphoton ionisation…
When an inverted ensemble of atoms is tightly packed on the scale of its emission wavelength or when the atoms are collectively strongly coupled to a single cavity mode, their dipoles will align and decay rapidly via a superradiant burst.…
Low frequency communication has a wide range of applications in the fields of satellite detection, underground mining, disaster relief. Rydberg atom sensor has rapidly developed in recent years, capitalizing on its calibration-free…
We consider two separate atoms interacting with a single-mode optical resonator. When the frequency of the resonator field is twice the atomic transition frequency, we show that there exists a resonant coupling between \textit{one} photon…
Motivated by recent interest in implementing circuit quantum electrodynamics with semiconducting quantum dots, we consider a double quantum dot (DQD) capacitively coupled to a superconducting resonator that is driven by the microwave field…
The resonant transfer of energy from the inversion sublevels in NH$_3$ to He atoms in triplet Rydberg states with principal quantum number $n=38$ has been controlled using electric fields below 15 V/cm in intrabeam collisions at…
We present a novel spectroscopic method for probing the \insitu~density of quantum gases. We exploit the density-dependent energy shift of highly excited {Rydberg} states, which is of the order $10$\MHz\,/\,1E14\,cm$^{\text{-3}}$ for…
We evaluate the performance and phase diffusion of trapped $^{87}$Rb atoms in an atom-chip sensor with Ramsey interferometry and Hahn's spin echo in the time and phase domains. We trace out how the phase uncertainty of interference fringes…
We demonstrate electromechanical coupling between a superfluid mechanical mode and a microwave mode formed by a patterned microfluidic chip and a 3D cavity. The electric field of the chip-cavity microwave resonator can be used to both drive…
Rydberg States are used in our One Atom Maser experiment because they offer a large dipole moment and couple strongly to low numbers of microwave photons in a high Q cavity. Here we report the absolute frequencies of the P$_{3/2}$ states…
We propose a new method to create two-photon states in a controllable way using interaction between the Rydberg atoms during the storage and retrieval of slow light. A distinctive feature of the suggested procedure is that the slow light is…
Coplanar waveguide resonators are central to the thriving field of circuit quantum electrodynamics. Recently, we have demonstrated the generation of a broadband microwave-frequency comb spectrum using a superconducting quantum interference…
Atomic-vapor sensors based on Rydberg atoms now face a transition towards practical applications, with several outstanding challenges. To achieve the best sensitivities, a superheterodyne mode of operation is desired, which requires the…
We realize a coherent transfer between a laser-accessible low-angular-momentum Rydberg state and the circular Rydberg level with maximal angular momentum. This transfer is induced by a radiofrequency field with a high-purity $\sigma^+$…
The complex Rydberg structure of ytterbium atoms is shaped by multiple low-lying ion-core-excited states and strong channel interactions, which presents both opportunities and challenges for quantum information processing and precision…
We have directly detected millimeter wave (mm-wave) free space superradiant emission from Rydberg states ($n \sim 30$) of barium atoms in a single shot. We trigger the cooperative effects with a weak initial pulse and detect with…