TY - JOUR
T1 - Spontaneous interlayer compression in commensurately stacked van der Waals heterostructures
AU - Pike, Nicholas A.
AU - Dewandre, Antoine
AU - Chaltin, François
AU - Garcia Gonzalez, Laura
AU - Pillitteri, Salvatore
AU - Ratz, Thomas
AU - Verstraete, Matthieu J.
N1 - Publisher Copyright:
© 2021 American Physical Society.
PY - 2021/6/15
Y1 - 2021/6/15
N2 - Interest in layered two-dimensional materials, particularly stacked heterostructures of transition-metal dichalcogenides, has led to the need for a better understanding of the structural and electronic changes induced by stacking. Here, we investigate the effects of idealized heterostructuring, with periodic commensurate stacking, on the structural, electronic, and vibrational properties, when compared to the counterpart bulk transition-metal dichalcogenide. We find that in heterostructures with dissimilar chalcogen species there is a strong compression of the interlayer spacing, compared to the bulk compounds. This compression of the heterostructure is caused by an increase in the strength of the induced polarization interaction between the layers, but not a full charge transfer. We argue that this effect is real, not due to the imposed commensurability, and should be observable in heterostructures combining different chalcogens. Interestingly, we find that incommensurate stacking of Ti-based dichalcogenides can lead to the stabilization of the charge-density wave phonon mode, which is unstable in the 1T phase at low temperature. Mixed Ti- and Zr-based heterostructures are still dynamically unstable, but TiS2/ZrS2 becomes ferroelectric.
AB - Interest in layered two-dimensional materials, particularly stacked heterostructures of transition-metal dichalcogenides, has led to the need for a better understanding of the structural and electronic changes induced by stacking. Here, we investigate the effects of idealized heterostructuring, with periodic commensurate stacking, on the structural, electronic, and vibrational properties, when compared to the counterpart bulk transition-metal dichalcogenide. We find that in heterostructures with dissimilar chalcogen species there is a strong compression of the interlayer spacing, compared to the bulk compounds. This compression of the heterostructure is caused by an increase in the strength of the induced polarization interaction between the layers, but not a full charge transfer. We argue that this effect is real, not due to the imposed commensurability, and should be observable in heterostructures combining different chalcogens. Interestingly, we find that incommensurate stacking of Ti-based dichalcogenides can lead to the stabilization of the charge-density wave phonon mode, which is unstable in the 1T phase at low temperature. Mixed Ti- and Zr-based heterostructures are still dynamically unstable, but TiS2/ZrS2 becomes ferroelectric.
UR - http://www.scopus.com/inward/record.url?scp=85108022236&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.103.235307
DO - 10.1103/PhysRevB.103.235307
M3 - Article
AN - SCOPUS:85108022236
SN - 2469-9950
VL - 103
JO - Physical Review B
JF - Physical Review B
IS - 23
M1 - 235307
ER -