Exact nonequilibrium steady state of $XXZ$ circuits boundary driven with arbitrary resets or fields

Popkov, Vladislav (author), Prosen, Tomaž (author)

We propose a spatially inhomogeneous matrix product Ansatz for an exact many-body density operator of a boundary-driven $XXZ$ quantum circuit. The Ansatz has formally infinite bond dimension and is fundamentally different from previous constructions. The circuit is driven by a pair of reset quantum channels applied on the boundary qubits, which polarize the qubits to arbitrary pure target states. Moreover, one of the reset channels can be replaced by an arbitrary local unitary gate, thus representing a hybrid case with coherent and incoherent driving. Analyzing the Ansatz, we obtain a family of relatively robust separable nonequilibrium steady states, which can be viewed as a circuit extension of spin-helix states and are particularly suited for experimental investigations.

• Language: English
• Keywords: quantum mechanics, quantum circuits, open quantum systems
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: Str. 070401-1-070401-7
• Numbering: Vol. 135, iss. 7
• PID: 20.500.12556/RUL-175241
• UDC: 530.145
• ISSN on article: 0031-9007
• DOI: 10.1103/31p7-lcgh
• COBISS.SI-ID: 254347267
• Publication date in RUL: 22.10.2025

Record is a part of a journal

• Title: Physical review letters
• Shortened title: Phys. rev. lett.
• Publisher: American Physical Society
• ISSN: 0031-9007
• COBISS.SI-ID: 1282575

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: kvantna mehanika, kvantna vezja, odprti kvantni sistemi