arXiv subjects

Jing-Yi Chen

Publications and source records attributed to Jing-Yi Chen.

4 recordsLinked to original sources

arXiv2026

Different roles of quantum interference in a quantum dot photocell with two intermediate bands

It is generally believed that quantum interference can improve the transport of photo-generated carriers in a photocell, thereby improve the photoelectric conversion efficiency. In this work, we explicitly explore different roles of quantum interferences in the photoelectric conversion efficiency in a quantum dot (QD) photocell with two intermediate bands. The increasing transition rates from different charge transport channels bring out first increasing, then decreasing, and then monotonically decreasing photoelectric conversion efficiencies. And the photoelectric conversions increase with quantum coherence generated by the upper transition rates owing to their robust quantum interference. However, the conversion efficiency decrease with the quantum interference induced by two lower-transition rates due to the shortened population lifetime in the intermediate bands. These results provide insight into different roles of quantum interferences in photoelectric conversion efficiency, and may provide some artificial strategies to achieve efficient photoelectric conversion via the adjusted quantum interferences in a QD photocell with multi-intermediate bands.

physics.app-ph↗

arXiv2024

Enhanced quantum yields and efficiency in a quantum dot photocell modeled by a multi-level system

To absorb the photons below the band-gap energy effectively, we proposed a quantum dot (QD) photocell modeled by multi-level system for the quantum yields and photo-to-charge efficiency limits. The theoretical results show the quantum yields are enhanced as compared to the single band-gap solar cell, and the photo-to-charge efficiencies are larger than Shockley and Queisser efficiency in the same absorbed spectrum. What's more, at the room temperature the efficiency limits are well beyond 63% achieved by Luque and Marti (Ref\cite{26}) due to absorbing the low-energy photons via two sub-bands in this proposed photocell system. The achievements may reveal a novel theoretical approach to enhance the QD photocell performance modeled a multi-level absorbing photons system.

cond-mat.mes-hall↗

arXiv2019

The suppressed radiative recombination rate in a quantum photocell with three electron donors

The radiative recombination of electron-hole pairs represents a great challenge to the photon-to-charge efficiency in the photocell. In this paper, we investigate how to suppress radiative recombination rate (RRR) in a proposed quantum photocell with three dipole-dipole coupled and uncoupled electron donors. The results showed that the RRR could be suppressed in this photocell with three uncoupled electron donors but be enhanced with three dipole-dipole coupled electron donors by the ambient circumstance temperatures, and the increasing energy gap in the donors, the decreasing gap between the donors and acceptor inhabited the RRR with three dipole-dipole both coupled and uncoupled electron donors. When the photocell was manipulated by the electrostatic dipole-dipole coupling strength J at room temperature, the RRR was suppressed to a smaller minimum by the gap between the donors and acceptor than those by different gaps in the donors. These suppressed strategies for RRR point out some significant ways to increase the photon-to-charge efficiency and deserve the further experimental verification.

cond-mat.mes-hall↗

arXiv2015

A "nearly parametric" solution to Selective Harmonic Elimination PWM

Selective Harmonic Elimination Pulse Width Modulation (SHEPWM) is an important technique to solve PWM problems, which control the output voltage of an inverter via selecting appropriate switching angles. Based on the Rational Univariate Representation (RUR) theory for solving polynomial systems, the paper presents an algorithm to compute a "nearly parametric" solution to a SHEPWM problem. When the number of switching angles N is fixed, a "nearly parametric" solution can be considered as functions of the modulation index m. So we can adapt the amplitude of the output voltage with the same source voltage by changing the modulation index. When m is given as a specific value, complete solutions to the SHEPWM problem can be obtained easily using univariate polynomial solving. Compared with other methods, m is considered as a symbolic parameter for the first time, and this can help avoid totally restarting when m changes. The average time for computing complete solutions associated to 460 modulation indexes based on a "nearly parametric" solution when N=5 is 0.0284s, so the algorithm is practical. Three groups of switching angles associated to N=5, m=0.75 is simulated in MATLAB, and it verifies the algorithm's correctness.

math.NA↗