Motivated by recent observations of fractional Chern insulators (FCIs) in the vicinity of superconducting (SC) phases, we study fractional quantum (anomalous) Hall-superconductor heterostructures in the presence of U(1) order-parameter fluctuations and particularly focus on the case of ν = 2/3 quantum Hall states leading to \({{\mathbb{Z}}}_{3}\) parafermions. We first employ a...
Nitrogen-vacancy (NV) center ensembles in diamond are one of the most promising solid-state quantum platforms for various sensing applications. Achieving ultimate sensitivity requires simultaneously long spin dephasing times (\({T}_{2}^{* }\)) and high NV center concentrations. In this work, we propose a systematic measurement approach to quantify the electron spin dephasing in...
The discovery of Tc ~ 80 K superconductivity in pressurized La3Ni2O7 has launched a new platform to study high-temperature superconductivity. Using non-perturbative dynamic cluster approximation quantum Monte Carlo calculations, we characterize the magnetic and superconducting pairing behavior of a realistic bilayer two-orbital Hubbard-Hund model of this system that describes the...
We demonstrate that applying modest magnetic fields (<0.1 T) during high-temperature crystal growth can profoundly alter the structure and ground state of a spin-orbit-coupled, antiferromagnetic trimer lattice. Using BaIrO₃ as a model system, whose ground state is intricately dictated by the trimer lattice, we show that magneto-synthesis, a field-assisted synthesis approach...
Recent experimental discoveries of infinite- and finite-layer nickelate superconductors have highlighted the importance of a single-band \({d}_{{x}^{2}-{y}^{2}}\) Fermi surface for enabling unconventional superconductivity similar to cuprates. Motivated by this, we use density functional theory (DFT) and dynamical mean-field theory (DMFT) to identify two infinite-layer fluorides...
The van der Waals antiferromagnet CrSBr exhibits coupling of vibrational, electronic, and magnetic degrees of freedom, giving rise to distinctive quasi-particle interactions. We investigate these interactions across a wide temperature range using polarization-resolved Raman spectroscopy at various excitation energies, complemented by optical absorption and photoluminescence...
Magnetoelectric multiferroics such as rare earth manganites host nonreciprocal behavior driven by low symmetry, spin-orbit coupling, and toroidal moments, although less has been done to explore whether lanthanides like Er3+ might extend functionality into the hard infrared for optical communications purposes. In this work, we reveal nonreciprocity in the f-manifold crystal field...
Long-range tunable strongly coupled photon-magnon systems are crucial for large-scale hybrid networks enabling coherent information processing. Here, we experimentally fabricate a photon-magnon system with a saturable gain, achieving long-range strong coupling in the linear regime for the first time, aside from the nonlinear regime. By modulating the propagation phase of...
Combination of altermagnetism and ferroic orders, such as ferroelectric switchable altermagnetism [Phys. Rev. Lett. 134, 106801 (2025) and Phys. Rev. Lett. 134, 106802 (2025)], offers a powerful route to achieve nonvolatile switching of altermagnetic spin splitting. In this work, by synergizing altermagnetism and ferroelasticity, we propose the concept of ferroelastic...
Experiments involving resonant optical excitation of infrared-active phonons in crystals have emerged as a powerful new way to tune materials properties. A puzzling and so far unexplained aspect of some so-called nonlinear phononics experiments is that the observed lifetimes of the optically created metastable phases are sometimes orders of magnitude longer than expected based on...
Cavity magnomechanical systems, which coherently couple magnons, photons, and phonons, offer a powerful platform for exploring quantum phenomena and developing hybrid quantum technologies. We study a non-Hermitian cavity magnomechanical system featuring a yttrium iron garnet (YIG) sphere driven by an external magnetic field, where magnons interact with cavity photons via magnetic...
Multi-orbital/band electronic structure and orbital-dependent electron correlations critically shape emergent electronic states in correlated materials. Bulk FeSe exemplifies this through its enigmatic nematic phase, whose microscopic mechanism remains an outstanding question. Here, we perform comprehensive 57Fe and 77Se nuclear magnetic resonance (NMR) study on the evolution of...
In superconductors with low superfluid density, superconducting phase fluctuations can significantly influence many physical properties. A quantitative microscopic description of electrical transport under thermal phase fluctuations has remained scarce. Using Monte Carlo simulations of the classical XY model, we investigate the numerically exact transport properties arising from...
The combination of a centrosymmetric crystallographic structure with local structural alternations and collinear antiferromagnetism can lead to broken PT (Parity × Time-reversal) symmetry, resulting in altermagnets with non-relativistic spin-split bands. The 6H perovskites with composition A3BB’2O9 exhibit unique layered structural alternations and typically adopt an...
Quantum geometry, characterized by the quantum geometric tensor, plays a central role in diverse physical phenomena in quantum materials. This pedagogical review introduces the concept and highlights its implications across multiple domains, including optical responses, Landau levels, fractional Chern insulators, superfluid weight, spin stiffness, exciton condensates, and...
Altermagnets are a novel class of magnetic materials that bridge the gap between ferromagnets (FMs) and antiferromagnets (AFMs). A key feature is the non-degeneracy of magnon modes where spin splitting occurs, leading to chirality and direction-dependent magnon dispersions governed by symmetry. We explore this in metallic g-wave altermagnets (TPn, where T = V, Cr; Pn = As, Sb, Bi...
Generalized Wigner crystals (GWC) on triangular moiré superlattices, formed from stacking two layers of transition metal chalcogenides, have been observed at multiple fractional fillings [Nature 587, 214–218 (2020), Nat. Phys. 17, 715–719 (2021), Nature 597, 650–654 (2021)]. Motivated by these experiments, tied with the need for accurate microscopic descriptions of these...
Magneto-optical measurements in La0.8Sr0.2NiO2 and Nd0.825Sr0.175NiO2 reveal an intriguing new facet of infinite-layer nickelate superconductors: the onset of spin-glass behavior at a temperature far exceeding the superconducting critical temperature Tc. This discovery sharply contrasts with copper oxide superconductors, where magnetism and superconductivity remain largely...
It is a distinct possibility that spin fluctuations are the pairing interactions in numerous unconventional superconductors. In the high-transition-temperature (high-Tc) cuprates, superconductivity emerges upon doping antiferromagnetic Mott insulators, and spin fluctuations might furthermore drive unusual pseudogap phenomena. Here we use magnetic neutron scattering to study the...
We develop a gauge-invariant renormalized mean-field theory (RMFT) to reliably find the quantum spin liquid (QSL) states and their field response for realistic Kitaev materials under strong magnetic fields and described by the generalized Kitaev J-K-Γ-\({\Gamma }^{{\prime} }\) model. Remarkably, while our RMFT reproduces previous results based on using more complicated numerical...
The 4d-electron trimer lattice Ba₄Nb₁₋ₓRu₃₊ₓO₁₂ exhibits either a quantum spin liquid (QSL) or a heavy-fermion strange metal (HFSM) phase, depending on Nb content. In the QSL state, itinerant spinons act as effective heat carriers, enhancing thermal conductivity. Strikingly, applying a magnetic field up to 14 T causes an abrupt, up-to-5000% increase in heat capacity below 150 mK...
At the quantum critical point of correlated materials, a non-Fermi liquid state appears where electron correlations continuously develop to very low temperatures. The relaxation time of the interacted electrons, namely quasiparticles, is scaled with the Planckian time, ℏ/kBT. However, there is a debate over whether heavy-fermion systems can obey the Planckian time. In the optical...
Inspired by empirical evidence of the existence of pair-density-wave (PDW) order in certain underdoped cuprates, we investigate the collective modes in systems with unidirectional PDW order with momenta ± Q and a d-wave form-factor with special focus on the amplitude (Higgs) modes. In the pure PDW state, there are two overdamped Higgs modes. We show that a phase with co-existing...