62 citations · 285 across the 13 of their papers we have counts for
13 papers
Basis dependence of Neural Quantum States for the Transverse Field Ising Model
Ronald Santiago Cortes, Aravindh S. Shankar, Marcello Dalmonte +2
Neural Quantum States (NQS) are powerful tools used to represent complex quantum many-body states in an increasingly wide range of applications. However, despite their popularity,…
Classical fracton spin liquid and Hilbert space fragmentation in a 2D spin- model
Nils Niggemann, Meghadeepa Adhikary, Yannik Schaden-Thillmann +1
Classical U(1) fracton spin liquids feature an extensive ground state degeneracy and follow an effective description in terms of a tensor Gauss' law where charges, so-called fracto…
Gapless fracton quantum spin liquid and emergent photons in a 2D spin-1 model
Nils Niggemann, Meghadeepa Adhikary, Yannik Schaden-Thillmann +1
Gapless fracton quantum spin liquids are exotic phases of matter described by higher-rank U(1) gauge theories which host gapped and immobile fracton matter excitations as well as g…
Phase diagram of the antiferromagnetic - spin- pyrochlore Heisenberg model
Imre Hagymási, Nils Niggemann, Johannes Reuther
We study the phase diagram of the antiferromagnetic - Heisenberg model on the pyrochlore lattice with spins at zero and finite temperatures. We use a combination of…
Temperature flow in pseudo-Majorana functional renormalization for quantum spins
Benedikt Schneider, Johannes Reuther, Matías G. Gonzalez +2
We implement the temperature flow scheme first proposed by Honerkamp and Salmhofer in Phys.~Rev.~B 64, 184516 (2001) into the pseudo-Majorana functional renormalization group metho…
$\require{mhchem}$Quantum paramagnetism in the decorated square-kagome antiferromagnet $\ce{Na6Cu7BiO4(PO4)4Cl3}$
Nils Niggemann, Nikita Astrakhantsev, Arnaud Ralko +9
$\require{mhchem}$The square-kagome lattice Heisenberg antiferromagnet is a highly frustrated Hamiltonian whose material realizations have been scarce. We theoretically investigate…
Pseudo-fermion functional renormalization group for spin models
Tobias Müller, Dominik Kiese, Nils Niggemann +5
For decades, frustrated quantum magnets have been a seed for scientific progress and innovation in condensed matter. As much as the numerical tools for low-dimensional quantum magn…
Quantum effects on unconventional pinch point singularities
Nils Niggemann, Yasir Iqbal, Johannes Reuther
Fracton phases are a particularly exotic type of quantum spin liquids where the elementary quasiparticles are intrinsically immobile. These phases may be described by unconventiona…
Pinch-points to half-moons and up in the stars: the kagome skymap
Dominik Kiese, Francesco Ferrari, Nikita Astrakhantsev +9
Pinch point singularities, associated with flat band magnetic excitations, are tell-tale signatures of Coulomb spin liquids. While their properties in the presence of quantum fluct…
Quantitative functional renormalization for three-dimensional quantum Heisenberg models
Nils Niggemann, Johannes Reuther, Björn Sbierski
We employ a recently developed variant of the functional renormalization group method for spin systems, the so-called pseudo Majorana functional renormalization group, to investiga…
Pinwheel valence-bond-crystal ground state of the spin- Heisenberg antiferromagnet on the lattice
Nikita Astrakhantsev, Francesco Ferrari, Nils Niggemann +9
We investigate the nature of the ground-state of the spin- Heisenberg antiferromagnet on the lattice by complementary state-of-the-art numerical techniques,…
Frustrated Quantum Spins at finite Temperature: Pseudo-Majorana functional RG approach
Nils Niggemann, Björn Sbierski, Johannes Reuther
The pseudofermion functional renormalization group (PFFRG) method has proven to be a powerful numerical approach to treat frustrated quantum spin systems. In its usual implementati…
Classical spiral spin liquids as a possible route to quantum spin liquids
Nils Niggemann, Max Hering, Johannes Reuther
Quantum spin liquids are long-range entangled phases whose magnetic correlations are determined by strong quantum fluctuations. While an overarching principle specifying the precis…