Related papers: Magnon Nesting in Driven Two-Dimensional Quantum M…
Nonlinear dynamics govern a wide array of natural phenomena and are essential for understanding nonequilibrium behaviors in condensed matter systems. In magnetically ordered materials, magnons - the quanta of spin waves - exhibit intrinsic…
We consider the coupling of the magnons in both quantum ferromagnets and antiferromagnets to the longitudinal order-parameter fluctuations, and the resulting nonanalytic behavior of the longitudinal susceptibility. In classical magnets it…
Rigidity of an ordered phase in condensed matter results in collective excitation modes spatially extending in macroscopic dimensions. Magnon is a quantum of an elementary excitation in the ordered spin system, such as ferromagnet. Being…
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…
We present a comprehensive analysis of the magnetic excitations and electronic properties of fully quantum double-exchange ferromagnets, i.e., systems where ferromagnetic ordering emerges from the competition between spin, charge, and…
Magnons can endow quantum devices with new functionalities. Assessing their potential requires precise characterization of magnon properties. Here, we use a superconducting qubit to probe magnons in a ferrimagnet over a range of about 2000…
We analyse the magnon spectrum and distribution function of the antiferromagnetic phase of the Floquet-driven Hubbard model. Above a critical drive strength, we find a dynamical instability, resulting from a change in sign of the magnon…
Microscopic theories of magnetoresistance have traditionally focused on momentum relaxation and the plasma frequency of itinerant electrons. Here, we uncover a distinct mechanism in which magnetoresistance originates from quantum…
We study parametric instability in a magnomechanical system, specifically examining magnon tunneling between moving ferromagnetic insulators. Our analysis reveals that quantum fluctuations generate spin currents above a critical velocity…
We propose a general mechanism of multiple-Q ordering with noncollinear and noncoplanar spin textures in itinerant magnets. By analyzing the fourth-order perturbation with respect to the spin-charge coupling, we find that the instability…
The apparently inimical relationship between magnetism and superconductivity has come under increasing scrutiny in a wide range of material classes, where the free energy landscape conspires to bring them in close proximity to each other.…
The ultrastrong coupling of (quasi-)particles has gained considerable attention due to its application potential and richness of the underlying physics. Coupling phenomena arising due to electromagnetic interactions are well explored. In…
We investigate an electromagnetic instability in two-dimensional materials arising from an anisotropy of the Fermi surface, utilizing a kinetic model accounting for the effects of the values of temperature, chemical potential and anisotropy…
We study the magnetic instability of gapless superconductors. The instability arises due to the infrared divergence associated with the gapless modes of the superconductor. When the Fermi-surface mismatch between pairing fermions is close…
We consider the parity invariant (2+1)-dimensional QED where the matter is represented as a mixture of fermions with opposite spins. It is argued that the perturbative ground state of the system is unstable with respect to the formation of…
In this work we study the propagations of normal frequency modes for quantum hydrodynamic (QHD) waves in the linear limit and introduce a new kind of instability in a double-degenerate plasma. Three different regimes, namely, low,…
Conventionally ordered magnets possess bosonic elementary excitations, called magnons. By contrast, no magnetic insulators in more than one dimension are known whose excitations are not bosons but fermions. Theoretically, some quantum spin…
N\'eel ordered antiferromagnets exhibit two-mode squeezing such that their ground state is a nonclassical superposition of magnon Fock states. Here we theoretically demonstrate that antiferromagnets can couple to spin qubits via direct…
We show that in the Anderson model for a two-dimensional non-Fermi liquid a magnetic instability can lead to the itinerant electron ferromagnetism. The critical temperature and the susceptibility of the paramagnetic phase have been…
We experimentally and theoretically demonstrate that nonlinear spin-wave dynamics can induce an effective resonant interaction between non-resonant magnon modes in a yttrium iron garnet disk. Under strong pumping near the ferromagnetic…