Details
| Original language | English |
|---|---|
| Pages (from-to) | 643-652 |
| Number of pages | 10 |
| Journal | Journal of alloys and compounds |
| Volume | 739 |
| Early online date | 28 Dec 2017 |
| Publication status | Published - 30 Mar 2018 |
| Externally published | Yes |
Abstract
Electride materials offer attractive physical properties due to their loosely bound electrons. Ca2N, an electride in the two-dimensional (2D) form was successfully recently synthesized. We conducted extensive first-principles calculations to explore the mechanical, electronic, optical and transport response of single-layer and free-standing Ca2N and Sr2N electrides to external strain. We show that Ca2N and Sr2N sheets present isotropic elastic properties with positive Poisson's ratios, however, they yield around 50% higher tensile strength along the zigzag direction as compared with armchair. We also showed that the strain has negligible effect on the conductivity of the materials; the current in the system reduces by less than 32% for the structure under ultimate uniaxial strain along the armchair direction. Compressive strain always increases the electronic transport in the systems due to stronger overlap of the atomic orbitals. Our results show that the optical spectra are anisotropic for light polarization parallel and perpendicular to the plane. Interband transition contributions along in-plane polarization are not negligible, by considering this effect the optical properties of Ca2N and Sr2N sheets in the low frequency regime significantly changed. The insight provided by this study can be useful for the future application of Ca2N and Sr2N in nanodevices.
Keywords
- 2D electride, CaN and SrN, Electronic, Mechanical, Optical
ASJC Scopus subject areas
- Engineering(all)
- Mechanics of Materials
- Engineering(all)
- Mechanical Engineering
- Materials Science(all)
- Metals and Alloys
- Materials Science(all)
- Materials Chemistry
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In: Journal of alloys and compounds, Vol. 739, 30.03.2018, p. 643-652.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Mechanical, optoelectronic and transport properties of single-layer Ca2N and Sr2N electrides
AU - Mortazavi, Bohayra
AU - Berdiyorov, Golibjon R.
AU - Shahrokhi, Masoud
AU - Rabczuk, Timon
N1 - Funding information: B. M. and T. R. greatly acknowledge the financial support by European Research Council for COMBAT project (Grant number 615132 ). G.R.B. acknowledges computational resources provided by the research computing center at Texas A&M University in Qatar.
PY - 2018/3/30
Y1 - 2018/3/30
N2 - Electride materials offer attractive physical properties due to their loosely bound electrons. Ca2N, an electride in the two-dimensional (2D) form was successfully recently synthesized. We conducted extensive first-principles calculations to explore the mechanical, electronic, optical and transport response of single-layer and free-standing Ca2N and Sr2N electrides to external strain. We show that Ca2N and Sr2N sheets present isotropic elastic properties with positive Poisson's ratios, however, they yield around 50% higher tensile strength along the zigzag direction as compared with armchair. We also showed that the strain has negligible effect on the conductivity of the materials; the current in the system reduces by less than 32% for the structure under ultimate uniaxial strain along the armchair direction. Compressive strain always increases the electronic transport in the systems due to stronger overlap of the atomic orbitals. Our results show that the optical spectra are anisotropic for light polarization parallel and perpendicular to the plane. Interband transition contributions along in-plane polarization are not negligible, by considering this effect the optical properties of Ca2N and Sr2N sheets in the low frequency regime significantly changed. The insight provided by this study can be useful for the future application of Ca2N and Sr2N in nanodevices.
AB - Electride materials offer attractive physical properties due to their loosely bound electrons. Ca2N, an electride in the two-dimensional (2D) form was successfully recently synthesized. We conducted extensive first-principles calculations to explore the mechanical, electronic, optical and transport response of single-layer and free-standing Ca2N and Sr2N electrides to external strain. We show that Ca2N and Sr2N sheets present isotropic elastic properties with positive Poisson's ratios, however, they yield around 50% higher tensile strength along the zigzag direction as compared with armchair. We also showed that the strain has negligible effect on the conductivity of the materials; the current in the system reduces by less than 32% for the structure under ultimate uniaxial strain along the armchair direction. Compressive strain always increases the electronic transport in the systems due to stronger overlap of the atomic orbitals. Our results show that the optical spectra are anisotropic for light polarization parallel and perpendicular to the plane. Interband transition contributions along in-plane polarization are not negligible, by considering this effect the optical properties of Ca2N and Sr2N sheets in the low frequency regime significantly changed. The insight provided by this study can be useful for the future application of Ca2N and Sr2N in nanodevices.
KW - 2D electride
KW - CaN and SrN
KW - Electronic
KW - Mechanical
KW - Optical
UR - http://www.scopus.com/inward/record.url?scp=85039989410&partnerID=8YFLogxK
U2 - 10.1016/j.jallcom.2017.12.276
DO - 10.1016/j.jallcom.2017.12.276
M3 - Article
AN - SCOPUS:85039989410
VL - 739
SP - 643
EP - 652
JO - Journal of alloys and compounds
JF - Journal of alloys and compounds
SN - 0925-8388
ER -