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تسجيل مستخدم جديدQuantum simulation of electronic structure with transcorrelated Hamiltonian: increasing accuracy without extra quantum resources
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Quantum simulations of electronic structure with transformed ab initio Hamiltonians that include some electron correlation effects a priori are demonstrated. The transcorrelated Hamiltonians used in this work are efficiently constructed classically, at polynomial cost, by an approximate similarity transformation with an explicitly correlated two-body unitary operator; they are Hermitian, include up to two-particle interactions, and are free of electron-electron singularities. To investigate whether the use of such transformed Hamiltonians can reduce resource requirements for general quantum solvers for the Schrodinger equation, we explore the accuracy and the computational cost of the quantum variational eigensolver, based on the unitary coupled cluster with singles and doubles (q-UCCSD). Our results demonstrate that transcorrelated Hamiltonians, paired with extremely compact bases, produce explicitly correlated energies comparable to those from much larger bases. The use of transcorrelated Hamiltonians reduces the number of CNOT gates by up to two orders of magnitude, and the number of qubits by a factor of three.
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