Quantum Computing with Exciton Qubits in Colloidal Semiconductor Nanocrystals

Harankahage, Dulanjan; Cassidy, James; Yang, Mingrui; Porotnikov, Dmitry; Williams, Maia; Kholmicheva, Natalia; Zamkov, Mikhail

doi:10.1021/acs.jpcc.1c05009

DOE OSTI · 1831439

Quantum Computing with Exciton Qubits in Colloidal Semiconductor Nanocrystals

Harankahage, Dulanjan·Cassidy, James·Yang, Mingrui·Porotnikov, Dmitry·Williams, Maia·Kholmicheva, Natalia·Zamkov, Mikhail

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Abstract

The present work evaluates the feasibility of quantum computing with exciton qubits in coupled colloidal semiconductor nanocrystals (NCs). A strategy for manipulating two-qubit states of colloidal NC hetero-dimers is described. We show that a sequence of laser pulses with the same photon energy can bring excitonic states of a nanocrystal hetero-dimer into entanglement and perform arbitrary qubit rotations (quantum gates). Our simulations of a realistic two-particle assembly of CdSe/CdS core/shell NCs demonstrate that such two-qubit gate operations can be driven by optical parametric oscillators with a theoretical error of 0.1%. Furthermore, a strategy for upscaling two-qubit hetero-dimers to N-qubit exciton gates in semiconductor NC assemblies is discussed.

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Harankahage, Dulanjan, Cassidy, James, Yang, Mingrui, Porotnikov, Dmitry, Williams, Maia, Kholmicheva, Natalia, Zamkov, Mikhail. 2021-10-04. Quantum Computing with Exciton Qubits in Colloidal Semiconductor Nanocrystals. https://doi.org/10.1021/acs.jpcc.1c05009

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