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arXiv · 2504.05332

Constrained Search in Imaginary Time

Markus Penz·Robert van Leeuwen
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Abstract

We introduce an imaginary-time evolution method to evaluate the pure-state constrained-search functional from density-functional theory formulated on finite lattices. Simultaneously, it yields a potential that produces a prescribed density of an eigenstate. Besides being a computational scheme, this allows one to gain theoretical insights into the density-potential mapping. The method can be generalized to the optimization of the expectation value of a general self-adjoint operator on a finite-dimensional Hilbert space under a finite number of expectation-value constraints for commuting self-adjoint operators.

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Markus Penz, Robert van Leeuwen. 2025-04-04. Constrained Search in Imaginary Time. https://doi.org/10.1103/g4ch-5x8m

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