English
Related papers

Related papers: Nagaoka ferromagnetism observed in a quantum dot p…

200 papers

We control quantum fluctuations to create the ground state magnetic phases of a classical Ising model with a tunable longitudinal magnetic field using a system of 6 to 10 atomic ion spins. Due to the long-range Ising interactions, the…

Atomistic simulations based on the first-principles of quantum mechanics are reaching unprecedented length scales. This progress is due to the growth in computational power allied with the development of new methodologies that allow the…

Materials Science · Physics 2021-05-19 Mariana Rossi

Simulating out-of-equilibrium dynamics of quantum field theories in nature is challenging with classical methods, but is a promising application for quantum computers. Unfortunately, simulating interacting bosonic fields involves a high…

The Falicov-Kimball model is a lattice model of itinerant spinless fermions ("electrons") interacting by an on-site potential with classical particles ("ions"). We continue the investigations of the crystalline ground states that appear for…

Condensed Matter · Physics 2008-02-03 Ch. Gruber , N. Macris , A. Messager , D. Ueltschi

Actinide compounds with 5f electrons have been attracting much attention because of their interesting magnetic and electronic properties such as heavy fermion state, unconventional superconductivity, co-existence of the superconductivity…

Strongly Correlated Electrons · Physics 2018-02-28 Naoyuki Tateiwa , Jiri Pospisil , Yoshinori Haga , Hironori Sakai , Tatsuma D. Matsuda , Etsuji Yamamoto

The Kondo effect in quantum dots (QDs) - artificial magnetic impurities - attached to ferromagnetic leads is studied with the numerical renormalization group (NRG) method. It is shown that the QD level is spin-split due to presence of…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 J. Martinek , M. Sindel , L. Borda , J. Barnaś , J. König , G. Schön , J. von Delft

Strongly out-of-equilibrium regimes in magnetic nanostructures exhibit novel properties, linked to the nonlinear nature of magnetization dynamics, which are of great fundamental and practical interest. Here, we demonstrate that field-driven…

Digital quantum computers offer a promising route for studying complex many-body systems that are otherwise inaccessible by their classical counterparts. Capabilities including mid-circuit measurements and feedback allow for simulating the…

We examine the magnetic correlations in quantum spin models that were derived recently as effective low-energy theories for electronic correlation effects on the edge states of graphene nanoribbons. For this purpose, we employ quantum Monte…

Mesoscale and Nanoscale Physics · Physics 2017-10-11 Cornelie Koop , Stefan Wessel

A comprehensive theory is developed that describes the coexistence of p-wave, spin-triplet superconductivity and itinerant ferromagnetism. It is shown how to use field-theoretic techniques to derive both conventional strong-coupling theory,…

Superconductivity · Physics 2009-02-06 T. R. Kirkpatrick , D. Belitz

We introduce a novel approach for the investigation of spin-wave excitations in itinerant ferromagnets. Our theory is based on a variational treatment of general multi-band Hubbard models which describe elements and compounds of transition…

Strongly Correlated Electrons · Physics 2009-10-31 J. Buenemann

We propose a near-term quantum simulator based on the fluxonium qubits inductively coupled to form a chain. This system provides long coherence time, large anharmonicity, and strong coupling, making it suitable to study Ising spin models.…

Quantum Physics · Physics 2021-04-08 A. Barış Özgüler , Vladimir E. Manucharyan , Maxim G. Vavilov

Simulating quantum many-body systems on a classical computer generally requires a computational cost that grows exponential with the number of particles. This computational complexity has been the main obstacle to understanding various…

Quantum Physics · Physics 2019-07-12 Jirawat Tangpanitanon , Dimitris G. Angelakis

Magnetic properties of materials ranging from conventional ferromagnetic metals to strongly correlated materials such as cuprates originate from Coulomb exchange interactions. The existence of alternate mechanisms for magnetism that could…

Advances in quantum technologies are often limited by slow device characterization, complex tuning requirements, and scalability challenges. Spin qubits in electrostatically defined quantum dots provide a promising platform but are not…

Large-scale simulations of the spin dynamics in quantum dots subjected to trains of periodic laser pulses enable us to describe and understand related experiments. By comparing the data for different models to experimental results, we gain…

Mesoscale and Nanoscale Physics · Physics 2022-01-10 Philipp Schering , Philipp W. Scherer , Götz S. Uhrig

We observe a low-lying sharp spin mode of three interacting electrons in an array of nanofabricated AlGaAs/GaAs quantum dots by means of resonant inelastic light scattering. The finding is enabled by a suppression of the inhomogeneous…

Mesoscale and Nanoscale Physics · Physics 2012-03-02 Andrea Gamucci , Vittorio Pellegrini , Achintya Singha , Aron Pinczuk , Loren N. Pfeiffer , Kenneth W. West , Massimo Rontani

Heavy fermion (HF) states emerge in correlated quantum materials due to the interplay between localized magnetic moments and itinerant electrons, but rarely appear in 3d-electron systems due to high itinerancy of d-electrons. Here, an…

Recently discovered advanced materials, such as heavy fermions, frequently exhibit a rich phase diagram suggesting the presence of different competing interactions. A unified description of the origin of these multiple interactions, albeit…

Strongly Correlated Electrons · Physics 2020-10-01 E. C. Marino , Lizardo H. C. M. Nunes

We introduce an elementary quantum system consisting of a set of spins on a graph and a particle hopping between its nodes. The quantum state is build sequentially, applying a unitary transformation that couples neighboring spins and, at a…

Quantum Physics · Physics 2019-01-23 Alberto D. Verga