Anomalous enhancement of carrier mobility by remote phonons

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Zhang, Chenmu, Liu, Yuanyue
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909663613681664
author Zhang, Chenmu
Liu, Yuanyue
author_facet Zhang, Chenmu
Liu, Yuanyue
contents Remote phonons from dielectrics are typically believed to degrade carrier mobility in adjacent semiconductors through Fröhlich scattering of polar-optical phonons (POPs). Here, we challenge this conventional view by demonstrating that in van der Waals (vdW) heterostructures, remote POPs can instead enhance the mobility. To this end, we developed a first-principles computational framework to evaluate these remote phonon effects. Applying our approach to an example of monolayer InSe semiconductor encapsulated by h-BN dielectric layers, we show that electron mobility is enhanced due to coupling between POPs in InSe and h-BN, which gives rise to a new collective phonon mode where their individual Fröhlich potentials partially cancel each other. Based on this insight, we further identified additional dielectrics that display similar mobility enhancement, demonstrating universality of mobility enhancement due to remote phonons. This work offers not only an effective computational method to evaluate the remote phonon effects but also new insights into mobility engineering in next-generation electronics.
format Preprint
id arxiv_https___arxiv_org_abs_2404_08114
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Anomalous enhancement of carrier mobility by remote phonons
Zhang, Chenmu
Liu, Yuanyue
Materials Science
Remote phonons from dielectrics are typically believed to degrade carrier mobility in adjacent semiconductors through Fröhlich scattering of polar-optical phonons (POPs). Here, we challenge this conventional view by demonstrating that in van der Waals (vdW) heterostructures, remote POPs can instead enhance the mobility. To this end, we developed a first-principles computational framework to evaluate these remote phonon effects. Applying our approach to an example of monolayer InSe semiconductor encapsulated by h-BN dielectric layers, we show that electron mobility is enhanced due to coupling between POPs in InSe and h-BN, which gives rise to a new collective phonon mode where their individual Fröhlich potentials partially cancel each other. Based on this insight, we further identified additional dielectrics that display similar mobility enhancement, demonstrating universality of mobility enhancement due to remote phonons. This work offers not only an effective computational method to evaluate the remote phonon effects but also new insights into mobility engineering in next-generation electronics.
title Anomalous enhancement of carrier mobility by remote phonons
topic Materials Science
url https://arxiv.org/abs/2404.08114