TY - JOUR

T1 - Symmetry-adapted calculations of strain and polarization fields in (111)-oriented zinc-blende quantum dots

AU - Schulz, S.

AU - Caro, M. A.

AU - O'Reilly, E. P.

AU - Marquardt, O.

PY - 2011/9/13

Y1 - 2011/9/13

N2 - We present expressions for the elastic and first-order piezoelectric tensor in (111)-oriented III-V zinc-blende semiconductors. Moreover, an equation for the second-order piezoelectric polarization vector in these systems is derived. Together these expressions provide an efficient route to calculate built-in potentials and strain fields in (111)-oriented zinc-blende nanostructures. Our detailed analysis provides insight into the key parameters that modify strain and built-in fields in a (111)-oriented zinc-blende system compared to a conventional (001) structure. We show that the calculated strain field in a (111)-oriented quantum dot displays the correct C3v symmetry of the underlying crystal structure, even though we use a continuum-based approach and the quantum dot geometry is higher in symmetry than C3v, e.g., C v. This behavior originates from an in-plane angle dependence of certain elastic tensor components in the (111)-zinc-blende system. In addition, we compare the elastic and the first-order piezoelectric tensor of the (111)-zinc-blende systems with the corresponding quantities in a wurtzite structure and point out similarities and differences. This comparison provides, for example, insight into the sign of the shear piezoelectric coefficient e 15 in the wurtzite system, which is still under debate in the literature. Our analysis indicates e15<0, in accordance with recent experimental and theoretical results.

AB - We present expressions for the elastic and first-order piezoelectric tensor in (111)-oriented III-V zinc-blende semiconductors. Moreover, an equation for the second-order piezoelectric polarization vector in these systems is derived. Together these expressions provide an efficient route to calculate built-in potentials and strain fields in (111)-oriented zinc-blende nanostructures. Our detailed analysis provides insight into the key parameters that modify strain and built-in fields in a (111)-oriented zinc-blende system compared to a conventional (001) structure. We show that the calculated strain field in a (111)-oriented quantum dot displays the correct C3v symmetry of the underlying crystal structure, even though we use a continuum-based approach and the quantum dot geometry is higher in symmetry than C3v, e.g., C v. This behavior originates from an in-plane angle dependence of certain elastic tensor components in the (111)-zinc-blende system. In addition, we compare the elastic and the first-order piezoelectric tensor of the (111)-zinc-blende systems with the corresponding quantities in a wurtzite structure and point out similarities and differences. This comparison provides, for example, insight into the sign of the shear piezoelectric coefficient e 15 in the wurtzite system, which is still under debate in the literature. Our analysis indicates e15<0, in accordance with recent experimental and theoretical results.

UR - http://www.scopus.com/inward/record.url?scp=80053902631&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.84.125312

DO - 10.1103/PhysRevB.84.125312

M3 - Article

AN - SCOPUS:80053902631

VL - 84

SP - 1

EP - 14

JO - Physical Review B (Condensed Matter and Materials Physics)

JF - Physical Review B (Condensed Matter and Materials Physics)

SN - 2469-9950

IS - 12

M1 - 125312

ER -