Reactions of radiation-induced electrons with carbon dioxide in inert cryogenic films: matrix tuning of the excess electron interactions in solids

2020 ◽  
Vol 22 (25) ◽  
pp. 14155-14161
Author(s):  
Ekaterina S. Shiryaeva ◽  
Irina A. Baranova ◽  
Daniil A. Tyurin ◽  
Vladimir I. Feldman

The attachment of radiation-induced electrons to carbon dioxide in inert solid films is controlled by the conduction band energy of quasi-free electrons in the medium.

2021 ◽  
Vol 7 (11) ◽  
pp. eabe4270 ◽  
Author(s):  
A. Ben Hayun ◽  
O. Reinhardt ◽  
J. Nemirovsky ◽  
A. Karnieli ◽  
N. Rivera ◽  
...  

It is a long-standing goal to create light with unique quantum properties such as squeezing and entanglement. We propose the generation of quantum light using free-electron interactions, going beyond their already ubiquitous use in generating classical light. This concept is motivated by developments in electron microscopy, which recently demonstrated quantum free-electron interactions with light in photonic cavities. Such electron microscopes provide platforms for shaping quantum states of light through a judicious choice of the input light and electron states. Specifically, we show how electron energy combs implement photon displacement operations, creating displaced-Fock and displaced-squeezed states. We develop the theory for consecutive electron-cavity interactions with a common cavity and show how to generate any target Fock state. Looking forward, exploiting the degrees of freedom of electrons, light, and their interaction may achieve complete control over the quantum state of the generated light, leading to novel light statistics and correlations.


2005 ◽  
Vol 865 ◽  
Author(s):  
Akimasa Yamada ◽  
Koji Matsubara ◽  
Keiichiro Sakurai ◽  
Shogo Ishizuka ◽  
Hitoshi Tampo Hajime ◽  
...  

AbstractThe reasons why the open circuit voltage (Voc) of high-x CuIn1-xGaxSe2 (CIGS)/ZnO solar cells remain low are discussed. Here it is shown that the Voc ceiling can be interpreted simply on the basis of a model that the valence-band energy (Ev) of CIGS is almost immovable irrespective of x. When the conduction-band energy (Ec) of ZnO is lower than that of high-x CIGS (DEc<0), the built-in potential (Vbi) of a CIGS/ZnO junction is equivalent to the flat-band potential (Vbi) that arises from the separation between the Fermi energies of the two materials. If the Ev (and therefore the Fermi energy) of p-type CIGS is constant with increasing x, the Vbi and Voc that follows the Vbi remain unchanged since the Fermi energy of ZnO is constant. This unchangeable Voc reduces the conversion efficiency of high-x CIGS cells in cooperation with reduced photocurrents due to a larger bandgap. A positive offset, ΔEc>o gives rise to a photoelectrons barrier in the conduction-band that partially cancels Voc, thus the Voc of a low-x CIGS cell is governed by the Ec of CIGS. Based upon this concept, a material selection guideline is given for the windows and transparent electrodes appropriate for high-x CIGS absorbers-based solar cells.


Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2639
Author(s):  
Nadine C. Michenfelder ◽  
Christian Gienger ◽  
Melina Dilanas ◽  
Andreas Schnepf ◽  
Andreas-Neil Unterreiner

We present a comprehensive femtosecond (fs) transient absorption study of the [Ge9(Hyp)3]− (Hyp = Si(SiMe3)3) cluster solvated in tetrahydrofuran (THF) with special emphasis on intra- and intermolecular charge transfer mechanisms which can be tuned by exchange of the counterion and by dimerization of the cluster. The examination of the visible and the near infrared (NIR) spectral range reveals four different processes of cluster dynamics after UV (267/258 nm) photoexcitation related to charge transfer to solvent and localized excited states in the cluster. The resulting transient absorption is mainly observed in the NIR region. In the UV-Vis range transient absorption of the (neutral) cluster core with similar dynamics can be observed. By transferring concepts of: (i) charge transfer to the solvent known from solvated Na− in THF and (ii) charge transfer in bulk-like materials on metalloid cluster systems containing [Ge9(Hyp)3]− moieties, we can nicely interpret the experimental findings for the different compounds. The first process occurs on a fs timescale and is attributed to localization of the excited electron in the quasi-conduction band/excited state which competes with a charge transfer to the solvent. The latter leads to an excess electron initially located in the vicinity of the parent cluster within the same solvent shell. In a second step, it can recombine with the cluster core with time constants in the picosecond (ps) timescale. Some electrons can escape the influence of the cluster leading to a solvated electron or after interaction with a cation to a contact pair both with lifetimes exceeding our experimentally accessible time window of 1 nanosecond (ns). An additional time constant on a tens of ps timescale is pronounced in the UV-Vis range which can be attributed to the recombination rate of the excited state or quasi conduction band of Ge9−. In the dimer, the excess electron cannot escape the molecule due to strong trapping by the Zn cation that links the two cluster cores.


1979 ◽  
Vol 71 (1) ◽  
pp. 550-551 ◽  
Author(s):  
Yoh‐ichi Yamaguchi ◽  
Toshitaka Nakajima ◽  
Masaru Nishikawa
Keyword(s):  

2019 ◽  
Vol 126 (8) ◽  
pp. 083106 ◽  
Author(s):  
M. Welna ◽  
Ł Janicki ◽  
W. M. Linhart ◽  
T. Tanaka ◽  
K. M. Yu ◽  
...  

2020 ◽  
Vol 5 (7) ◽  
pp. 2343-2348 ◽  
Author(s):  
Qiong Wang ◽  
Fengshuo Zu ◽  
Pietro Caprioglio ◽  
Christian M. Wolff ◽  
Martin Stolterfoht ◽  
...  

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