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Related papers: Optimal purification of thermal graph states

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The problem of simulating the thermal behavior of quantum systems remains a central open challenge in quantum computing. Unlike well-established quantum algorithms for unitary dynamics, \emph{provably efficient} algorithms for preparing…

Quantum Physics · Physics 2026-05-14 Dominik Hahn , Ryan Sweke , Abhinav Deshpande , Oles Shtanko

The ability to prepare desired states without allowing time for the atomic system to spontaneously decay to the ground state is limited by the fact that Hamiltonian controls cannot affect the purity of the state in question. In this paper,…

Quantum Physics · Physics 2017-08-28 Somayeh M. A. Mirzaee , Chitra Rangan

It is not a general opinion that that a quantum system could be purified into a target eigenstate via repeated measurements on a coupled qubit rather than direct transitions in the Hamiltonian. The projective measurement on the ancillary…

Quantum Physics · Physics 2023-10-30 Jia-shun Yan , Jun Jing

Ensuring a satisfactory statistical convergence of anharmonic thermodynamic properties requires sampling of many atomic configurations, however the methods to obtain those necessarily produce correlated samples, thereby reducing the…

Statistical Mechanics · Physics 2022-06-07 Erki Metsanurk

Quantum state purification is the task of recovering a nearly pure copy of an unknown pure quantum state using multiple noisy copies of the state. This basic task has applications to quantum communication over noisy channels and quantum…

Quantum Physics · Physics 2025-01-22 Andrew M. Childs , Honghao Fu , Debbie Leung , Zhi Li , Maris Ozols , Vedang Vyas

We propose a protocol for effectively implementing complex-balanced thermalization via Markovian processes on a quantum-circuit platform that couples the system with engineered reservoir qubits. The non-orthogonality of qubit eigenstates…

Quantum Physics · Physics 2026-01-09 Yiting Mao , Peigeng Zhong , Haiqing Lin , Xiaoqun Wang , Shijie Hu

We return to the question of how the choice of stabilizer generators affects the preservation of information on structures whose degenerate ground state encodes a classical redundancy code. Controlled-not gates are used to transform the…

Quantum Physics · Physics 2015-05-19 Yu Tomita , C. Ricardo Viteri , Kenneth R. Brown

Since linear-optical two-photon gates are inherently probabilistic, measurement-based implementations are particularly well suited for photonic platforms: a large highly-entangled photonic resource state, called a graph state, is consumed…

Quantum Physics · Physics 2023-05-03 Paul Hilaire , Leonid Vidro , Hagai S. Eisenberg , Sophia E. Economou

Quantum hypergraph states form a generalisation of the graph state formalism that goes beyond the pairwise (dyadic) interactions imposed by remaining inside the Gaussian approximation. Networks of such states are able to achieve…

Quantum Physics · Physics 2026-05-06 Abhijith Ravikumar , Darren W. Moore , Radim Filip

The unknown temperature of a sample may be estimated with minimal disturbance by putting it in thermal contact with an individual quantum probe. If the interaction time is sufficiently long so that the probe thermalizes, the temperature can…

Quantum Physics · Physics 2015-06-09 Luis A. Correa , Mohammad Mehboudi , Gerardo Adesso , Anna Sanpera

We present an algorithm that prepares thermal Gibbs states of one dimensional quantum systems on a quantum computer without any memory overhead, and in a time significantly shorter than other known alternatives. Specifically, the time…

Quantum Physics · Physics 2010-10-29 Ersen Bilgin , Sergio Boixo

We propose a quantum algorithm for the purification of a generic mixed state $\rho$ of a $n$-qudit system by using an ancillary $n$-qudit system. The algorithm is optimal in that (i) the number of ancillary qudits cannot be reduced, (ii)…

Quantum Physics · Physics 2009-05-04 Giuliano Benenti , Giuliano Strini

We develop the partitioning technique for quantum discrete systems. The graph consists of several subgraphs: a central graph and several branch graphs, with each branch graph being rooted by an individual node on the central one. We show…

Quantum Physics · Physics 2011-06-27 L. Jin , Z. Song

We develop a method to transform a collection of higher-dimensional spin systems from the thermal state with a very high temperature of a local spin-s Hamiltonian to a low-lying energy eigenstate of the same. The procedure utilizes an…

Quantum Physics · Physics 2024-09-16 Debkanta Ghosh , Tanoy Kanti Konar , Aditi Sen De

Oscillator Ising machines (OIMs) are networks of coupled oscillators that seek the minimum energy state of an Ising model. Since many NP-hard problems are equivalent to the minimization of an Ising Hamiltonian, OIMs have emerged as a…

Optimization and Control · Mathematics 2026-02-20 Ahmed Allibhoy , Arthur N. Montanari , Fabio Pasqualetti , Adilson E. Motter

We propose new quantum algorithms for thermal and ground state preparation based on system-bath interactions. These algorithms require only forward evolution under a system-bath Hamiltonian in which the bath is a single reusable ancilla…

Quantum Physics · Physics 2025-12-19 Zhiyan Ding , Yongtao Zhan , John Preskill , Lin Lin

Calculating the physical properties of quantum thermal states is a difficult problem for classical computers, rendering it intractable for most quantum many-body systems. A quantum computer, by contrast, would make many of these…

Strongly Correlated Electrons · Physics 2019-11-19 John Martyn , Brian Swingle

Providing the microscopic behavior of a thermalization process has always been an intriguing issue. There are several models of thermalization, which often requires interaction of the system under consideration with the microscopic…

Quantum Physics · Physics 2019-07-24 Prathik J Cherian , Sagnik Chakraborty , Sibasish Ghosh

While freestanding clean graphene is essential for various applications, existing technologies for removing the polymer layer after transfer of graphene to the desired substrate still leave significant contaminations behind. We discovered a…

Materials Science · Physics 2015-06-11 Jean-Nicolas Longchamp , Conrad Escher , Hans-Werner Fink

In this work we show that the simple Hamiltonians used in Quantum Graphity models are highly degenerate, having multiple ground states that are not lattices. In order to assess the distance of the resulting graphs from a lattice graph, we…

Statistical Mechanics · Physics 2018-08-20 Yoav Spector , Moshe Schwartz