| 1. |
- Anttu, Nicklas, et al.
(författare)
-
Absorption of light in InP nanowire arrays
- 2014
-
Ingår i: Nano Reseach. - : Springer Science and Business Media LLC. - 1998-0124 .- 1998-0000. ; 7:6, s. 816-823
-
Tidskriftsartikel (refereegranskat)abstract
- An understanding of the absorption of light is essential for efficient photovoltaic and photodetection applications with III-V nanowire arrays. Here, we correlate experiments with modeling and verify experimentally the predicted absorption of light in InP nanowire arrays for varying nanowire diameter and length. We find that 2,000 nm long nanowires in a pitch of 400 nm can absorb 94% of the incident light with energy above the band gap and, as a consequence, light which in a simple ray-optics description would be travelling between the nanowires can be efficiently absorbed by the nanowires. Our measurements demonstrate that the absorption for long nanowires is limited by insertion reflection losses when light is coupled from the air top-region into the array. These reflection losses can be reduced by introducing a smaller diameter to the nanowire-part closest to the air top-region. For nanowire arrays with such a nanowire morphology modulation, we find that the absorptance increases monotonously with increasing diameter of the rest of the nanowire.
|
|
| 2. |
- Espinet-Gonzalez, Pilar, et al.
(författare)
-
Nanowire Solar Cells : A New Radiation Hard PV Technology for Space Applications
- 2020
-
Ingår i: IEEE Journal of Photovoltaics. - 2156-3381. ; 10:2, s. 502-507
-
Tidskriftsartikel (refereegranskat)abstract
- Radiation hard thin-film solar cell technologies are necessary in order to achieve a step forward in the specific power of solar arrays for space applications. In this article, we analyze the degradation of nanowire (NW) solar cells under high energy particles. GaAs NW solar cells have been irradiated with protons of 100 and 350 keV at different fluences. The radiation hardness of the NW solar cells in all the cases is remarkable in comparison with GaAs planar solar cells and prior literature. Design guidelines to optimize the specific power of NW solar cells for space applications by jointly increasing their efficiency and radiation hardness are presented.
|
|
| 3. |
- Lebedev, A. V., et al.
(författare)
-
Psychedelic drug use and schizotypy in young adults
- 2021
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- Despite recently resurrected scientific interest in classical psychedelics, few studies have focused on potential harms associated with abuse of these substances. In particular, the link between psychedelic use and psychotic symptoms has been debated while no conclusive evidence has been presented. Here, we studied an adult population (n=1032) with a special focus on young (18-35 years) and healthy individuals (n=701) to evaluate the association of psychedelic drug use with schizotypy and evidence integration impairment typically observed in psychosis-spectrum disorders. Experimental behavioural testing was performed in a subsample of the subjects (n=39). We observed higher schizotypy scores in psychedelic users in the total sample. However, the effect size was notably small and only marginally significant when considering young and healthy subjects (Cohen's d=0.13). Controlling for concomitant drug use, none of our analyses found significant associations between psychedelic use and schizotypal traits. Results from experimental testing showed that total exposure to psychedelics (frequency and temporal proximity of use) was associated with better evidence integration (Cohen's d=0.13) and a higher sensitivity of fear responses (Cohen's d=1.05) to the effects instructed knowledge in a reversal aversive learning task modelled computationally with skin conductance response and pupillometry. This effect was present even when controlling for demographics and concomitant drug use. On a group level, however, only difference in sensitivity of fear responses to instructed knowledge reached statistical significance. Taken together, our findings suggest that psychedelic drug use is only weakly associated with psychosis-like symptoms, which, in turn, is to a large extent explained by psychiatric comorbidities and use of other psychoactive substances. Our results also suggest that psychedelics may have an effect on flexibility of evidence integration and aversive learning processes, that may be linked to recently suggested therapeutic effects of psychedelic drugs in non-psychotic psychiatric populations.
|
|
| 4. |
|
|
| 5. |
- Wallentin, Jesper, et al.
(författare)
-
InP Nanowire Array Solar Cells Achieving 13.8% Efficiency by Exceeding the Ray Optics Limit.
- 2013
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 339:6123, s. 1057-1060
-
Tidskriftsartikel (refereegranskat)abstract
- Photovoltaics based on nanowire arrays could reduce cost and materials consumption compared to planar devices, but have exhibited low efficiency of light absorption and carrier collection. We fabricated a variety of millimeter-sized arrays of p-i-n doped InP nanowires and found that the nanowire diameter and the length of the top n-segment were critical for cell performance. Efficiencies up to 13.8% (comparable to the record planar InP cell) were achieved using resonant light trapping in 180-nanometer-diameter nanowires that only covered 12% of the surface. The share of sunlight converted into photocurrent (71%) was six times the limit in a simple ray optics description. Furthermore, the highest open circuit voltage of 0.906 volt exceeds that of its planar counterpart, despite about 30 times higher surface-to-volume ratio of the nanowire cell.
|
|
| 6. |
- Zhang, Yuwei, et al.
(författare)
-
UV exposure : A novel processing method to fabricate nanowire solar cells
- 2019
-
Ingår i: 2019 IEEE 46th Photovoltaic Specialists Conference, PVSC 2019. - 0160-8371. - 9781728104942 ; , s. 2646-2648
-
Konferensbidrag (refereegranskat)abstract
- We demonstrate a novel and rapid method for nanowire (NW) solar cell processing. NW arrays were embedded in photoresist. The strong absorption of light in the NWs leads to self-limited exposure of the resist, which enables selective removal of the exposed part of the resist, opening up for the tips of the NWs and further processing. The UV-exposure technology allows a fast and low-cost process compared to the conventional reactive ion etching method.
|
|
