Quantum Dot Luminescent Concentrator Cavity Exhibiting 30-fold Concentration

• DOI: 10.1021/acsphotonics.5b00334
• Publication Date: 2015-08-17T12:22:54Z
• Authors: Noah D. Bronstein; Yuan Yao; Lu Xu; Erin O’Brien; Alexander S. Powers; Vivian E. Ferry; A. Paul Alivisatos; Ralph G. Nuzzo
• Keywords: 02 engineering and technology; 0210 nano-technology; 7. Clean energy

Luminescent solar concentrators doped with CdSe/CdS quantum dots provide a potentially low-cost and high-performance alternative to costly high-band-gap III–V semiconductor materials to serve as a top junction in multijunction photovoltaic devices for efficient utilization of blue photons. In this study, a photonic mirror was coupled with such a luminescent waveguide to form an optical cavity where emitted luminescence was trapped omnidirectionally. By mitigating escape cone and scattering losses, 82% of luminesced photons travel the length of the waveguide, creating a concentration ratio of 30.3 for blue photons in a waveguide with a geometric gain of 61. Further, we study the photon transport inside the luminescent waveguide, showing unimpeded photon collection across the entire length of the waveguide.