arXiv subjects

Yuexing Xia

Publications and source records attributed to Yuexing Xia.

4 recordsLinked to original sources

arXiv2026

Reconfigurable ultrafast perovskite polariton logic gates via nonlinear dynamics

Exciton-polaritons provide a great platform for developing ultrafast all-optical logic gates for quantum and optical chips. However, progress toward practical polariton logic remains limited due to incomplete logical functionality on a single device. Herein, we present a single-device perovskite polariton platform enabling reconfigurable, ultrafast logic gates with functional completeness. The device consists of an optically trapped perovskite microwire, generating well-controlled non-equilibrium polariton condensation states for multiple logic operation channels. By tailoring the power of signal and gate beams, the same device is programmed to execute three basic Boolean functions (AND,OR,and NOT) and a high-order XOR function with a high on/off ratio of 21 dB, and a fast response time 6.7 ps. The reconfigurability arises from the selective activation of different nonlinear responses of polariton condensates, including amplification, seeding state transitions, and nonlinear interaction. These results provide valuable insights for advancing exciton-polariton logic gates.

physics.optics↗

arXiv2025

Ultrafast Exciton-Polariton Transport and Relaxation in Halide Perovskite

Halide perovskites offer a great platform for room-temperature exciton-polaritons (EPs) due to their strong oscillator strength and large exciton binding energy, promising applications in next-generation photonic and polaritonic devices. Efficient manipulation of EP transport and relaxation is critical for device performance, yet their spatiotemporal dynamics across different in-plane momenta (k//) remain poorly understood due to limitations in experimental access. In this work, we employ energy-resolved transient reflectance microscopy (TRM) combined with the dispersion relation of EPs to achieve high-resolution imaging of EP transport at specific k//. This approach directly reveals the quasi-ballistic transport and ultrafast relaxation of EPs in different k// regions, showcasing diffusion as fast as ~490 cm2/s and a relaxation time of ~95.1 fs. Furthermore, by tuning the detuning parameter, we manipulate the ballistic transport group velocity and relaxation time of EPs across varying k//. Our results reveal key insights into the dynamics of EP transport and relaxation, providing valuable guidance for the design and optimization of polaritonic devices.

cond-mat.mtrl-sci↗

arXiv2025

All-optical and ultrafast control of high-order exciton-polariton orbital modes

Exciton-polaritons flows within closed quantum circuits can spontaneously form phase-locked modes that carry orbital angular momentum (OAM). With its infinite set of angular momentum quantum numbers, high-order OAM represents a transformative solution to the bandwidth bottleneck in multiplexed optical communication. However, its practical application is hindered by the limited choice of materials which in general requires cryogenic temperatures and the reliance on mechanical switching. In this work, we achieve stable and high-order (up to order of 33) OAM modes by constructing a closed quantum circuit using the halide perovskite microcavities at room temperature. By controlling the spatial and temporal symmetry of the closed quantum circuits using another laser pulse, we achieve significant tuning OAM of EP flows from 8 to 12. Our work demonstrate all-optical and ultrafast control of high-order OAM using exciton-polariton condensates in perovskite microcavities that would have important applications in high-throughput optical communications.

physics.optics↗

arXiv2024

Ultrafast carriers' separation imaging in WS2-WSe2 in plane heterojunction by transient reflectivity microscopy

Carrier transport in nanodevices plays a crucial role in determining their functionality. In the post-Moore era, the behavior of carriers near surface or interface domains the function of the whole devices. However, the femtosecond dynamics and nanometer-scale movement of carriers pose challenges for imaging their behavior. Techniques with high spatial-temporal resolution become imperative for tracking their intricate dynamics. In this study, we employed transient reflectivity microscopy to directly visualize the charge separation in the atomic interface of WS2-WSe2 in-plane heterojunctions. The carriers' drifting behavior was carefully tracked, enabling the extraction of drift velocities of 30 nm/ps and 10.6 nm/ps for electrons and holes. Additionally, the width of the depletion layer was determined to be 300 nm based on the carriers' moving trajectory. This work provides essential parameters for the potential effective utilization of these covalent in-plane heterojunctions,and demonstrates the success of transient optical imaging in unraveling the electrical behavior of nano devices, paving the way for a new avenue of electro-optical analysis.

cond-mat.mes-hall↗