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Sheng-Xian Xiao

Publications and source records attributed to Sheng-Xian Xiao.

4 recordsLinked to original sources

Electromagnetically Induced Transparency Spectra of Ladder Four-Level System with Quantum Frequency Mixing

In this paper, we generalized the quantum frequency mixing technology to a ladder-type four-level system and studied its effect on electromagnetically induced transparency spectra. We found a secondary splitting of Autler-Townes splitting in the probing field transmission spectra, which could be understood by the effective Hamiltonian derived with multi-mode Floquet theory. The Frequency mixing scheme developed here enables continuous tunablity of the resonant frequency between upper levels, which facilitates the broad band sensing of AC field. Furthermore, by introducing an additional periodic driving, we realize an effective model that two distinct quantum interference effects coexist: interference among Floquet channels and loop interference arising from closed coherent pathways. Both interference effects could be read out from the transmission spectra independently. The changing of the distance between double splitting peaks represents the interference of Floquet channels, while their asymmetric linewidth broadening is linked with the total effective phase of the loop. This not only provides complementary readout for extracting the phase of AC field, but also establishes a new paradigm for coherent control in multi-level quantum systems.

quant-ph↗

Rydberg atomic spectrum analyzer with microwave-dressed-state-locking and multimode Floquet theory

We propose a Rydberg atomic spectrum analyzer (RASA) utilizing microwave-dressed-state-locking (MWDSL) in conjunction with multimode Floquet theory (MFT). By leveraging a strong local microwave (MW) field resonant with Rydberg states to implement MWDSL, we analyze the second-order effect of MFT induced by the interplay of controllable bias and signal MW fields. This effect facilitates the coupling of locked dressed states, providing a pathway for measuring the signal MW field. We demonstrate that the RASA can simultaneously characterize multiple MW fields across distinct frequencies, with both the frequency and strength of each MW field discernible in the spectral response. This capability renders RASA suitable for measuring unknown-frequency MW fields, thereby expanding the utility of Rydberg atom-based electrometers in complex spectral analysis scenarios.

physics.atom-ph↗

Continuously Expanding the Response Frequency of Rydberg Atom-Based Microwave Sensor by Using Quantum Mixer

Microwave electric (MW) field measurements utilizing Rydberg atoms have witnessed significant advancements, achieving remarkable sensitivity, albeit limited to discrete MW frequencies resonant with Rydberg states. Recently, various continuous-frequency measurement schemes have emerged. However, when the MW detuning surpasses 1 GHz, the sensitivity degrades by over an order of magnitude compared to resonant measurements. In this paper, we successfully extend the response frequency range by harnessing a controlled driving field in conjunction with a quantum mixer and heterodyne technology, theoretically enabling infinite scalability. Notably, second-order effects stemming from quantum mixing necessitate careful consideration to ensure accurate electric field measurements. In addition, compared to resonant measurements, the sensitivity decline for far-detuned MW fields exceeding 1 GHz is less than twice, representing a significant improvement of several orders of magnitude over alternative schemes. Furthermore, the sensitivity of far-detuned MW fields can be efficiently enhanced by augmenting the intensity and frequency of the controlled field. For detunings ranging from 100 MHz to 2 GHz, we present optimal sensitivity values and the corresponding methods to achieve them. Our findings pave the way for Rydberg atom-based MW receivers characterized by both high sensitivity and an exceptionally broad bandwidth.

quant-ph↗

Rabi Spectroscopy of Super-Bloch Oscillations in Optical Lattice Clock

Super-Bloch oscillations(SBOs) is giant Bloch oscillations (BOs) when applying both static and periodically driving force to free atoms in lattice at the condition that Bloch oscillations are close to integer times of driving frequencies. Rather than observe SBOs in real space, this paper presents a method to observe it using Rabi spectroscopy of Optical lattice clock(OLC). An effective model of OLC with atoms been added both static and time-periodical forces is derived. Based on that, we propose an experimental scheme and give the Rabi spectrum under lab achievable parameters. Utilizing the precision spectroscopy of OLC, force with a large range could be accurately measured by measuring the Period of SBOs. We also gave the best parameter condition of measuring gravity by calculating Fisher information. Our work paves the way to study other exotic dynamics behaviors in Floquet driving OLC.

quant-ph↗