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Related papers: Phonon decay in silicon nanocrystals

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Fully-inorganic cesium lead halide perovskite nanocrystals (NCs) have shown to exhibit outstanding optical properties such as wide spectral tunability, high quantum yield, high oscillator strength as well as blinking-free single photon…

The nonlinear photoacoustic response of indium phosphide nanocrystals on silicon nanotip arrays is investigated using time-resolved optical pump-probe spectroscopy and synchrotron-based X-ray diffraction. Femtosecond laser excitation…

Our direct atomic simulations reveal that a thermally activated phonon mode involves a large population of elastic wavepackets. These excitations are characterized by a wide distribution of lifetimes and coherence times expressing particle-…

Mesoscale and Nanoscale Physics · Physics 2021-05-26 Zhongwei Zhang , Yangyu Guo , Marc Bescond , Jie Chen , Masahiro Nomura , Sebastian Volz

The creation and evolution of nonequilibrium phonons is central in applications ranging from cosmological particle searches to decoherence processes in qubits. However, the fundamental understanding of decoherence pathways for athermal…

Materials Science · Physics 2023-10-18 Thomas F. Harrelson , Ibrahim Hajar , Omar A. Ashour , Sinéad M. Griffin

Silicon nanocrystals (SiNCs) have been under active investigation in the last decades and have been considered as a promising candidate for many optoelectronic applications including highly-efficient solar cells. Some of the fundamental…

Materials Science · Physics 2020-06-25 Marios Zacharias , Pantelis C. Kelires

The femtosecond optical pump-probe technique was used to study dynamics of photoexcited electrons and coherent optical phonons in transition metals Zn and Cd as a function of temperature and excitation level. The optical response in time…

Strongly Correlated Electrons · Physics 2009-11-11 Muneaki Hase , Kunie Ishioka , Jure Demsar , Kiminori Ushida , Masahiro Kitajima

From an investigation of the optical conductivity of FeSi single crystals using FTIR spectroscopy in the frequency range from 30 to 20000 wavenumbers we conclude that the transverse effective charge of the Fe and Si ions is approximately…

Strongly Correlated Electrons · Physics 2009-10-28 A. Damascelli , K. Schulte , D. van der Marel , A. A. Menovsky

The capture of photoexcited hot electrons in semiconductors before they lose their excess energy to cooling is a long-standing goal in photon energy conversion. Semiconductor nanocrystals have large electron energy spacings that are…

Fast quantum oscillations of a charge qubit in a double quantum dot fabricated in a Si/SiGe heterostructure are demonstrated and characterized experimentally. The measured inhomogeneous dephasing time T2* ranges from 127ps to ~2.1ns; it…

We investigate photoinization, energy deposition, plasma formation and the ultrafast optical breakdown in crystalline silicon irradiated by intense near-infrared laser pulses with pulse duration $\tau \le $ 100 fs. The occurrence of…

Materials Science · Physics 2021-11-24 Tzveta Apostolova , Boyan Obreshkov

Coherent and squeezed phonon oscillations can be excited in solids impulsively by a single femtosecond pulse whose duration is shorter that a phonon period. By applying the second ultrafast pump pulse these oscillations can be…

Mesoscale and Nanoscale Physics · Physics 2013-04-30 O. V Misochko

A patterned Si nanobeam is formed which supports co-localized acoustic and optical resonances that are coupled via radiation pressure. Starting from a bath temperature of T=20K, the 3.68GHz nanomechanical mode is cooled into its quantum…

Micro- and nanomechanical resonators have emerged as promising platforms for sensing a broad range of physical properties such as mass, force, torque, magnetic field, and acceleration. The sensing performance relies critically on the…

We consider electron(hole)-phonon coupling in crystalline organic semiconductors, using naphthalene for our case study. Employing a first-principles approach, we compute the changes in the self-consistent Kohn-Sham potential corresponding…

Strongly Correlated Electrons · Physics 2012-09-20 Nenad Vukmirovic , C. Bruder , Vladimir M. Stojanovic

Silicon carbide (SiC) is a wide band gap semiconductor with a variety of industrial applications. Among its many useful properties is its high thermal conductivity, which makes it advantageous for thermal management applications. In this…

Materials Science · Physics 2017-05-25 Nakib Haider Protik , Ankita Katre , Lucas Lindsay , Jesús Carrete , Natalio Mingo , David Broido

Pure dephasing of an exciton in a small quantum dot by optical and acoustic phonons is calculated using the ``independent boson model''. Considering the case of zero temperature the dephasing is shown to be only partial which manifests…

Condensed Matter · Physics 2009-11-07 E. Pazy

We calculate the current-voltage characteristic of metallic nanotubes at high bias voltage showing that a bottleneck exists for short nanotubes in contrast to large ones. We attribute this to a redistribution of lower-lying acoustic phonons…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Juergen Dietel , Hagen Kleinert

Rapid progress in silicon photonics has fostered numerous chip-scale sensing, computing, and signal processing technologies. However, many crucial filtering and signal delay operations are difficult to perform with all-optical devices.…

We theoretically study the relaxation of electron orbital states of a double quantum dot system due to two-phonon processes. In particular, we calculate how the relaxation rates depend on the separation distance between the quantum dots,…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 V. N. Stavrou , Xuedong Hu

Anharmonic effects in an atomic monolayer thin crystal with honeycomb lattice structure are investigated by analytical and numerical lattice dynamical methods. Starting from a semi-empirical model for anharmonic couplings of third and…

Materials Science · Physics 2015-05-20 K. H. Michel , S. Costamagna , F. M. Peeters
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