TY - JOUR
T1 - Electric-field tuning of the valley splitting in silicon corner dots
AU - Ibberson, D. J.
AU - Bourdet, L.
AU - Abadillo-Uriel, J. C.
AU - Ahmed, I.
AU - Barraud, S.
AU - Calderón, M. J.
AU - Niquet, Y. M.
AU - Gonzalez-Zalba, M. F.
PY - 2018
Y1 - 2018
N2 - We perform an excited state spectroscopy analysis of a silicon corner
dot in a nanowire field-effect transistor to assess the electric field
tunability of the valley splitting. First, we demonstrate a
back-gate-controlled transition between a single quantum dot and a
double quantum dot in parallel which allows tuning the device into
corner dot formation. We find a linear dependence of the valley
splitting on back-gate voltage, from 880 μeV to 610 μeV with a slope of −45 ± 3 μeV/V (or equivalently a slope of −48 ± 3 μeV/(MV/m)
with respect to the effective field). The experimental results are
backed up by tight-binding simulations that include the effect of
surface roughness, remote charges in the gate stack, and discrete
dopants in the channel. Our results demonstrate a way to electrically
tune the valley splitting in silicon-on-insulator-based quantum dots, a
requirement to achieve all-electrical manipulation of silicon spin
qubits.
AB - We perform an excited state spectroscopy analysis of a silicon corner
dot in a nanowire field-effect transistor to assess the electric field
tunability of the valley splitting. First, we demonstrate a
back-gate-controlled transition between a single quantum dot and a
double quantum dot in parallel which allows tuning the device into
corner dot formation. We find a linear dependence of the valley
splitting on back-gate voltage, from 880 μeV to 610 μeV with a slope of −45 ± 3 μeV/V (or equivalently a slope of −48 ± 3 μeV/(MV/m)
with respect to the effective field). The experimental results are
backed up by tight-binding simulations that include the effect of
surface roughness, remote charges in the gate stack, and discrete
dopants in the channel. Our results demonstrate a way to electrically
tune the valley splitting in silicon-on-insulator-based quantum dots, a
requirement to achieve all-electrical manipulation of silicon spin
qubits.
UR - http://www.scopus.com/inward/record.url?scp=85051120973&partnerID=8YFLogxK
U2 - 10.1063/1.5040474
DO - 10.1063/1.5040474
M3 - Letter (Academic Journal)
AN - SCOPUS:85051120973
VL - 113
JO - Applied Physics Letters
JF - Applied Physics Letters
SN - 0003-6951
IS - 5
M1 - 053104
ER -