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Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Spatial confined hot carrier dynamics for beyond unity quantum efficiency detection
Yu Wan1, Zhe Cheng1, Zhen Wang2
1Department of Physics, School of Physics and Materials Science, Nanchang University, Nanchang, China.
None:
Photon harvesting and conversion in semiconductors hold critical scientific and technological value due to their wide-ranging applications, including optoelectronics, renewable energy, and thermal management. However, the efficiency of optical-to-electrical energy conversion is fundamentally limited by the rapid relaxation of thermalized carriers. Here, we demonstrate a spatial confinement-controlled hot carrier dynamics in a T-shape lead selenide photo-thermoelectric device, which achieves a room temperature external quantum efficiency values exceeding unity. This enhancement arises from spatial confinement-induced local phonon scattering, which suppresses the optical-excited hot carrier relaxation. As a result, the T-shape lead selenide detector achieves a room temperature peak detectivity of 6.3 × 1010 cm Hz1/2 W-1 beyond thermoelectric theoretical limit. This work establishes a transformative pathway for achieving high-efficiency photodetection and energy conversion technologies.
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