Optoelectronic analysis of multijunction wire array solar cells

Turner-Evans, Daniel B.; Chen, Christopher T.; Emmer, Hal S.; McMahon, William E.; Atwater, Harry A.

doi:10.1063/1.4812397

Cited by 10 publications

(11 citation statements)

References 24 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Excluding this result, we conclude that for a fixed period, J sc increases as microwire length increases. 23 This effect is more pronounced in higher PFF, which is as expected.…”

Section: Resultssupporting

confidence: 83%

“…The EQE results, as depicted in Figure 4(d), also showed negligible change as a result of sidewall smoothening. It should be noted that rough sidewalls do provide the benefit of better light absorption due to good coupling of incident light, 23 but this benefit is offset by poorer minority carrier collection in these microwires resulting in no significant change in J sc performance between rough and smooth samples.…”

Section: Resultsmentioning

confidence: 99%

“…This GaNP solar cell's efficiency is higher than other wide-bandgap solar cells: 2.42% 19 for an indirect bandgap GaP (2.26 eV), 3.89% 20 for direct bandgap InGaP (2.12 eV), and 4.8% 21 for direct bandgap GaAsP (1.92 eV). Although there are studies focused on the integration of III-V onto Si wires, [22][23][24][25] to the best of our knowledge, no similar studies have fabricated and discussed GaNP microwire solar cells to date.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Radial direct bandgap p-i-n GaNP microwire solar cells with enhanced short circuit current

Sukrittanon

Liu

Breeden³

et al. 2016

Journal of Applied Physics

View full text Add to dashboard Cite

We report the demonstration of dilute nitride heterostructure core/shell microwire solar cells utilizing the combination of top-down reactive-ion etching to create the cores (GaP) and molecular beam epitaxy to create the shells (GaNP). Systematic studies of cell performance over a series of microwire lengths, array periods, and microwire sidewall morphologies examined by transmission electron microscopy were conducted to shed light on performance-limiting factors and to optimize the cell efficiency. We show by microscopy and correlated external quantum efficiency characterization that the open circuit voltage is degraded primarily due to the presence of defects at the GaP/GaNP interface and in the GaNP shells, and is not limited by surface recombination. Compared to thin film solar cells in the same growth run, the microwire solar cells exhibit greater short circuit current but poorer open circuit voltage due to greater light absorption and number of defects in the microwire structure, respectively. The comprehensive understanding presented in this work suggests that performance benefits of dilute nitride microwire solar cells can be achieved by further tuning of the epitaxial quality of the underlying materials.

show abstract

“…Excluding this result, we conclude that for a fixed period, J sc increases as microwire length increases. 23 This effect is more pronounced in higher PFF, which is as expected.…”

Section: Resultssupporting

confidence: 83%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Radial direct bandgap p-i-n GaNP microwire solar cells with enhanced short circuit current

Sukrittanon

Liu

Breeden³

et al. 2016

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…[1][2][3] To boost photovoltaic performance towards the Shockley-Queisser (SQ) limit, 4,5 effectively controlling the behaviors of photons and carriers within the SCs are critical. 6 However, one can hardly avoid the actual performance degradation arising from the impurity and trapping densities of semiconductor materials, 7 leading to the prominent photocurrent loss and voltage reduction.…”

Section: Introductionmentioning

confidence: 99%

Optoelectronic insights into the photovoltaic losses from photocurrent, voltage, and energy perspectives

Shang

et al. 2017

AIP Advances

View full text Add to dashboard Cite

Photocurrent and voltage losses are the fundamental limitations for improving the efficiency of photovoltaic devices. It is indeed that a comprehensive and quantitative differentiation of the performance degradation in solar cells will promote the understanding of photovoltaic physics as well as provide a useful guidance to design highly-efficient and cost-effective solar cells. Based on optoelectronic simulation that addresses electromagnetic and carrier-transport responses in a coupled finite-element method, we report a detailed quantitative analysis of photocurrent and voltage losses in solar cells. We not only concentrate on the wavelength-dependent photocurrent loss, but also quantify the variations of photocurrent and operating voltage under different forward electrical biases. Further, the device output power and power losses due to carrier recombination, thermalization, Joule heat, and Peltier heat are studied through the optoelectronic simulation. The deep insight into the gains and losses of the photocurrent, voltage, and energy will contribute to the accurate clarifications of the performance degradation of photovoltaic devices, enabling a better control of the photovoltaic behaviors for high performance.

show abstract

“…Other examples where numerical-based optimizations can be ineffective include 3D complex structures with anisotropic dielectric response and coupled electro-optical simulations. A coupled solution for the drift-diffusion model and the Maxwell's equations is necessary in order to achieve a more accurate modeling for optoelectronics [33,34]. Nonetheless, this is extremely time-consuming and inadequate for repeated runs using an optimization algorithm.…”

Section: Introductionmentioning

confidence: 99%

Experimentally-implemented genetic algorithm (Exp-GA): toward fully optimal photovoltaics

Zhong¹,

Fu²,

Ju³

et al. 2015

Opt. Express

View full text Add to dashboard Cite

The geometry and dimension design is the most critical part for the success in nano-photonic devices. The choices of the geometrical parameters dramatically affect the device performance. Most of the time, simulation is conducted to locate the suitable geometry, but in many cases simulation can be ineffective. The most pronounced examples are large-area randomized patterns for solar cells, light emitting diode (LED), and thermophtovoltaics (TPV). The large random pattern is nearly impossible to calculate and optimize due to the extended CPU runtime and the memory limitation. Other scenarios that numerical simulations become ineffective include three-dimensional complex structures with anisotropic dielectric response. This leads to extended simulation time especially for the repeated runs during its geometry optimization. In this paper, we show that by incorporating genetic algorithm (GA) into real-world experiments, shortened trial-and-error time can be achieved. More importantly, this scheme can be used for many photonic design problems that are unsuitable for simulation-based optimizations. Moreover, the experimentally implemented genetic algorithm (Exp-GA) has the additional advantage that the resultant objective value is a real one rather than a theoretical one. This prevents the gaps between the modeling and the fabrication due to the process variation or inaccurate numerical models. Using TPV emitters as an example, 22% enhancement in the mean objective value is achieved.

show abstract

Optoelectronic analysis of multijunction wire array solar cells

Cited by 10 publications

References 24 publications

Radial direct bandgap p-i-n GaNP microwire solar cells with enhanced short circuit current

Radial direct bandgap p-i-n GaNP microwire solar cells with enhanced short circuit current

Optoelectronic insights into the photovoltaic losses from photocurrent, voltage, and energy perspectives

Experimentally-implemented genetic algorithm (Exp-GA): toward fully optimal photovoltaics

Contact Info

Product

Resources

About