Exact parameterization of fermionic wave functions via unitary coupled cluster theory
Abstract
A formal analysis is conducted on the exactness of various forms of unitary coupled cluster (UCC) theory based on particle-hole excitation and de-excitation operators. Both the conventional single exponential UCC parameterization and a factorized (referred to here as "disentangled") version are considered. We formulate a differential cluster analysis to determine the UCC amplitudes corresponding to a general quantum state. The exactness of conventional UCC (ability to represent any state) is explored numerically, and it is formally shown to be determined by the structure of the critical points of the UCC exponential mapping. A family of disentangled UCC wave functions is proven to exactly parameterize any state, thus showing how to construct Trotter-error-free parameterizations of UCC for applications in quantum computing. From these results, we construct an exact disentangled UCC parameterization that employs an infinite sequence of particle-hole or general one- and two-body substitution operators.
Additional Information
© 2019 Published under license by AIP Publishing. Submitted: 22 October 2019; Accepted: 4 December 2019; Published Online: 26 December 2019. The authors were supported by the U.S. Department of Energy under Award No. DE-SC0019374. G.E.S. is a Welch Foundation Chair (C-0036). This work has benefitted from helpful discussions with Dominika Zgid, Nicholas Mayhall, Edwin Barnes, and Piotr Piecuch.Attached Files
Published - 1.5133059.pdf
Accepted Version - 1910.10130.pdf
Files
Name | Size | Download all |
---|---|---|
md5:cbb07e747bd868afd6658e0aebb5488c
|
4.8 MB | Preview Download |
md5:11fd9c2e5e5fb14ba2cba60b350f7a8e
|
4.0 MB | Preview Download |
Additional details
- Eprint ID
- 100449
- Resolver ID
- CaltechAUTHORS:20200102-100501259
- Department of Energy (DOE)
- DE-SC0019374
- Robert A. Welch Foundation
- C-0036
- Created
-
2020-01-02Created from EPrint's datestamp field
- Updated
-
2021-11-16Created from EPrint's last_modified field