scispace - formally typeset
Search or ask a question
Topic

Effective mass (solid-state physics)

About: Effective mass (solid-state physics) is a research topic. Over the lifetime, 12539 publications have been published within this topic receiving 295485 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, the influence of surface modification of Cu2O with varying thickness of SrTiO3 on photoelectrochemical (PEC) water splitting was investigated, and it was shown that the electrons in the modified thin films had large effective masses.
Abstract: Nanostructured thin films of Cu2O modified by overlayering SrTiO3 with varying thickness have been studied for the first time as photoelectrode in photoelectrochemical (PEC) water splitting. Effective mass calculations for electrons and holes in bulk SrTiO3 and Cu2O using DFT first-principles have also been attempted to explain the enhanced charge separation at Cu2O/SrTiO3 interface. All samples were characterized using XRD, SEM, and UV–vis spectrometry. The influence of surface modification of Cu2O with varying thickness of SrTiO3 on PEC performance has been investigated. Photocurrent density for Cu2O/SrTiO3 heterojunction with overall thickness of 343 nm at 0.8 V/SCE was found to be 2.52 mA cm–2 which is 25 times higher than that of pristine Cu2O (0.10 mA cm–2 at 0.8 V/SCE). Theoretical studies showed that the electrons in SrTiO3 had large effective masses as compared to electrons in Cu2O at conduction band minima indicating weak mobility of photogenerated electrons in SrTiO3 and strong mobility in Cu2O...

86 citations

Journal ArticleDOI
TL;DR: In this paper, the steady-state and transient electron transport in bulk wurtzite InN was analyzed using a revised set of material parameters, taking into account this recently observed phenomenology.
Abstract: Recent experimentation, performed on bulk wurtzite InN, suggests that the energy gap, the effective mass of the electrons in the lowest-energy valley, and the nonparabolicity coefficient of the lowest-energy valley are not as originally believed for this material. Using a semiclassical three-valley Monte Carlo simulation approach, we analyze the steady-state and transient electron transport that occurs within bulk wurtzite InN using a revised set of material parameters, this revised set of parameters taking into account this recently observed phenomenology. We find that the peak electron drift velocity is considerably greater than that found previously. The impact that this revised set of parameters has upon the transient electron transport is also found to be significant.

86 citations

Journal ArticleDOI
TL;DR: In this article, the authors investigated the accuracy of different transfer matrix approaches, widely used to solve the stationary effective mass Schrodinger equation for arbitrary one-dimensional potentials, and showed that a symmetrized transfer matrix approach yields a similar accuracy as the Airy function method at a significantly reduced numerical cost.
Abstract: The accuracy of different transfer matrix approaches, widely used to solve the stationary effective mass Schrodinger equation for arbitrary one-dimensional potentials, is investigated analytically and numerically. Both the case of a constant and a position dependent effective mass are considered. Comparisons with a finite difference method are also performed. Based on analytical model potentials as well as self-consistent Schrodinger-Poisson simulations of a heterostructure device, it is shown that a symmetrized transfer matrix approach yields a similar accuracy as the Airy function method at a significantly reduced numerical cost, moreover avoiding the numerical problems associated with Airy functions.

86 citations

Journal ArticleDOI
TL;DR: In this paper, a 2D hole gas of high mobility (5 × 105 cm2 V−1 s−1) is demonstrated in a very shallow strained germanium (Ge) channel, which is located only 22 nm below the surface.
Abstract: Buried-channel semiconductor heterostructures are an archetype material platform for the fabrication of gated semiconductor quantum devices. Sharp confinement potential is obtained by positioning the channel near the surface; however, nearby surface states degrade the electrical properties of the starting material. Here, a 2D hole gas of high mobility (5 × 105 cm2 V−1 s−1) is demonstrated in a very shallow strained germanium (Ge) channel, which is located only 22 nm below the surface. The top-gate of a dopant-less field effect transistor controls the channel carrier density confined in an undoped Ge/SiGe heterostructure with reduced background contamination, sharp interfaces, and high uniformity. The high mobility leads to mean free paths ≈ 6 µm, setting new benchmarks for holes in shallow field effect transistors. The high mobility, along with a percolation density of 1.2 × 1011cm−2, light effective mass (0.09me), and high effective g-factor (up to 9.2) highlight the potential of undoped Ge/SiGe as a low-disorder material platform for hybrid quantum technologies.

86 citations

Journal ArticleDOI
TL;DR: First-principles calculations of carrier dynamics in GaN are presented, focusing on electron-phonon (e-ph) scattering and the cooling and nanoscale dynamics of hot carriers, finding that e-ph scattering is significantly faster for holes compared to electrons and for hot carriers with an initial 0.5-1 eV excess energy.
Abstract: GaN is a key material for lighting technology. Yet, the carrier transport and ultrafast dynamics that are central in GaN light-emitting devices are not completely understood. We present first-principles calculations of carrier dynamics in GaN, focusing on electron–phonon (e-ph) scattering and the cooling and nanoscale dynamics of hot carriers. We find that e-ph scattering is significantly faster for holes compared to electrons and that for hot carriers with an initial 0.5–1 eV excess energy, holes take a significantly shorter time (∼0.1 ps) to relax to the band edge compared to electrons, which take ∼1 ps. The asymmetry in the hot carrier dynamics is shown to originate from the valence band degeneracy, the heavier effective mass of holes compared to electrons, and the details of the coupling to different phonon modes in the valence and conduction bands. We show that the slow cooling of hot electrons and their long ballistic mean free paths (over 3 nm at room temperature) are a possible cause of efficiency...

86 citations


Network Information
Related Topics (5)
Band gap
86.8K papers, 2.2M citations
91% related
Magnetization
107.8K papers, 1.9M citations
91% related
Electron
111.1K papers, 2.1M citations
90% related
Quantum dot
76.7K papers, 1.9M citations
89% related
Scattering
152.3K papers, 3M citations
88% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202215
2021410
2020421
2019395
2018362
2017412