Two-Body Interacting Silicon Quantum Dots array: Coherent and Dephasing-Limited Entanglement
Poster-In-person · Withdrawn
Abstract
H. Zapparoli1, F. M. Souza1
1- Institute of Physics, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38408-100, Brazil.
e-mails: hzappaneto@ufu.br, fmsouza@ufu.br
Linear chains of quantum dots (QDs) enable tunable parameters that allow the formation of qubits and entanglement [1]. We study a system of three QDs described by a tight-binding basis and, in order to make quantum computation and quantum information analyzes, we perform fermion-to-qubit mapping [2], accounting for on-site Coulomb repulsion. The system is initialized in the state |001111⟩ with two electrons of opposite spin on the first site. Solving the von Neumann equation, we compute occupations, fidelity and entanglement quantifiers. In the regime where Coulomb blockade prevents occupation of the intermediate site, the electrons undergo a virtual transition to the third site, producing the effective coupling between sites 1 and 3 obtained via perturbation theory. The dynamics show evolution toward the maximally entangled state (|001111⟩ + |111100⟩)/√2, demonstrating entanglement between the edge sites in the double-occupancy regime. When dephasing is included through the non-unitary term of the master equation, both negativity and von Neumann entropy display attenuated maxima, as expected.
1- Institute of Physics, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38408-100, Brazil.
e-mails: hzappaneto@ufu.br, fmsouza@ufu.br
Linear chains of quantum dots (QDs) enable tunable parameters that allow the formation of qubits and entanglement [1]. We study a system of three QDs described by a tight-binding basis and, in order to make quantum computation and quantum information analyzes, we perform fermion-to-qubit mapping [2], accounting for on-site Coulomb repulsion. The system is initialized in the state |001111⟩ with two electrons of opposite spin on the first site. Solving the von Neumann equation, we compute occupations, fidelity and entanglement quantifiers. In the regime where Coulomb blockade prevents occupation of the intermediate site, the electrons undergo a virtual transition to the third site, producing the effective coupling between sites 1 and 3 obtained via perturbation theory. The dynamics show evolution toward the maximally entangled state (|001111⟩ + |111100⟩)/√2, demonstrating entanglement between the edge sites in the double-occupancy regime. When dephasing is included through the non-unitary term of the master equation, both negativity and von Neumann entropy display attenuated maxima, as expected.
–
· 290 Publication: [1] K. W. Chan et al., Nano Lett. 21, 1517 (2021)
[2] F. M. Souza and L. Sanz, Phys. Rev. A 96, 052110 (2017)
Presenters
-
HELIO NETO
- Universidade Federal de Uberlândia