How to define quantum mean-field solvable Hamiltonians using Lie
algebras
- URL: http://arxiv.org/abs/2008.06633v3
- Date: Fri, 11 Jun 2021 02:17:56 GMT
- Title: How to define quantum mean-field solvable Hamiltonians using Lie
algebras
- Authors: Artur F. Izmaylov and Tzu-Ching Yen
- Abstract summary: We define what mean-field theory is, independently of a Hamiltonian realization in a particular set of operators.
We then formulate a criterion for a Hamiltonian to be mean-field solvable.
For the electronic Hamiltonians, our approach reveals the existence of mean-field solvable Hamiltonians of higher fermionic operator powers than quadratic.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Necessary and sufficient conditions for quantum Hamiltonians to be exactly
solvable within mean-field theories have not been formulated so far. To resolve
this problem, first, we define what mean-field theory is, independently of a
Hamiltonian realization in a particular set of operators. Second, using a
Lie-algebraic framework we formulate a criterion for a Hamiltonian to be
mean-field solvable. The criterion is applicable for both distinguishable and
indistinguishable particle cases. For the electronic Hamiltonians, our approach
reveals the existence of mean-field solvable Hamiltonians of higher fermionic
operator powers than quadratic. Some of the mean-field solvable Hamiltonians
require different sets of quasi-particle rotations for different eigenstates,
which reflects a more complicated structure of such Hamiltonians.
Related papers
- Determining non-Hermitian parent Hamiltonian from a single eigenstate [0.0]
We show that it can be sufficient to determine a non-Hermitian Hamiltonian from a single right or left eigenstate.
Our scheme favours non-Hermitian Hamiltonian learning on experimental quantum systems.
arXiv Detail & Related papers (2024-08-28T13:23:47Z) - Quantifying non-Hermiticity using single- and many-particle quantum properties [14.37149160708975]
The non-Hermitian paradigm of quantum systems displays salient features drastically different from Hermitian counterparts.
We propose a formalism that quantifies the (dis-)similarity of these right and left ensembles, for single- as well as many-particle quantum properties.
Our findings can be instrumental in unveiling new exotic quantum phases of non-Hermitian quantum many-body systems.
arXiv Detail & Related papers (2024-06-19T13:04:47Z) - Coherence generation with Hamiltonians [44.99833362998488]
We explore methods to generate quantum coherence through unitary evolutions.
This quantity is defined as the maximum derivative of coherence that can be achieved by a Hamiltonian.
We identify the quantum states that lead to the largest coherence derivative induced by the Hamiltonian.
arXiv Detail & Related papers (2024-02-27T15:06:40Z) - Exactly solvable Hamiltonian fragments obtained from a direct sum of Lie
algebras [0.0]
Exactly solvable Hamiltonians are useful in the study of quantum many-body systems using quantum computers.
We apply more general classes of exactly solvable qubit Hamiltonians than previously considered to address the Hamiltonian measurement problem.
arXiv Detail & Related papers (2024-02-14T18:22:45Z) - Recovery of a generic local Hamiltonian from a degenerate steady state [11.567029926262476]
Hamiltonian Learning (HL) is essential for validating quantum systems in quantum computing.
HL success depends on the Hamiltonian model and steady state.
We analyze HL for a specific type of steady state composed of eigenstates with degenerate mixing weight.
arXiv Detail & Related papers (2023-09-01T08:40:50Z) - Fermionic Hamiltonians without trivial low-energy states [12.961180148172197]
We construct local fermionic Hamiltonians with no low-energy trivial states (NLTS)
Distinctly from the qubit case, we define trivial states via finite-depth $textitfermionic$ quantum circuits.
We define a fermionic analogue of the class quantum PCP and discuss its relation with the qubit version.
arXiv Detail & Related papers (2023-07-25T18:00:02Z) - Extension of exactly-solvable Hamiltonians using symmetries of Lie
algebras [0.0]
We show that a linear combination of operators forming a modest size Lie algebra can be substituted by determinants of the Lie algebra symmetries.
The new class of solvable Hamiltonians can be measured efficiently using quantum circuits with gates that depend on the result of a mid-circuit measurement of the symmetries.
arXiv Detail & Related papers (2023-05-29T17:19:56Z) - Sparse random Hamiltonians are quantumly easy [105.6788971265845]
A candidate application for quantum computers is to simulate the low-temperature properties of quantum systems.
This paper shows that, for most random Hamiltonians, the maximally mixed state is a sufficiently good trial state.
Phase estimation efficiently prepares states with energy arbitrarily close to the ground energy.
arXiv Detail & Related papers (2023-02-07T10:57:36Z) - Iterative Quantum Optimization with Adaptive Problem Hamiltonian [19.4417702222583]
We describe an iterative algorithm in which a solution obtained with such a restricted problem Hamiltonian is used to define a new problem Hamiltonian that is better suited than the previous one.
In numerical examples of the shortest vector problem, we show that the algorithm with a sequence of improved problem Hamiltonians converges to the desired solution.
arXiv Detail & Related papers (2022-04-28T12:04:03Z) - Simultaneous Stoquasticity [0.0]
Stoquastic Hamiltonians play a role in the computational complexity of the local Hamiltonian problem.
We address the question of whether two or more Hamiltonians may be made simultaneously stoquastic via a unitary transformation.
arXiv Detail & Related papers (2022-02-17T19:08:30Z) - A simple approach to characterizing band topology in bosonic pairing
Hamiltonians [0.0]
We revisit the problem of characterizing band topology in dynamically-stable quadratic bosonic Hamiltonians that do not conserve particle number.
We show this problem can be rigorously addressed by a smooth and local adiabatic mapping procedure to a particle number conserving Hamiltonian.
Our approach shows that particle non-conserving bosonic Hamiltonians can be classified using known approaches for fermionic models.
arXiv Detail & Related papers (2021-04-13T04:40:19Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.