Related papers: Noise studies of magnetization dynamics in dilute …
We study the properties of heterostructures formed by two layers of diluted magnetic semiconductor separated by a nonmagnetic semiconductor layer. We find that there is a RKKY-type exchange coupling between the magnetic layers that oscilles…
The 1/f resistance noise of a two-dimensional (2D) hole system in a high mobility GaAs quantum well has been measured on both sides of the 2D metal-insulator transition (MIT) at zero magnetic field (B=0), and deep in the insulating regime.…
The static conductivity of the dilute magnetic semiconductor GaMnAs is calculated using the memory function formalism and time-dependent density-functional theory to account for impurity scattering and to treat Hartree and exchange…
We study NbTiN resonators by measurements of the temperature dependent resonance frequency and frequency noise. Additionally, resonators are studied covered with SiOx dielectric layers of various thicknesses. The resonance frequency…
Combined resistance noise and muon-spin relaxation ($\mu$SR) measurements of the ferromagnetic semiconductor HgCr$_2$Se$_4$ suggest a degree of magnetoelectric coupling and provide evidence for the existence of isolated magnetic polarons.…
We present a systematic numerical modeling investigation of magnetization dynamics and thermal magnetic moment fluctuations of single magnetic domain nanoparticles in a configuration applicable to enhancing inductive magnetic resonance…
We develop a theory for two-dimensional diluted magnetic semiconductor systems (e.g. $\textrm{Ga}_{1-x}\textrm{Mn}_{x}\textrm{As}$ layers) where the itinerant carriers mediating the ferromagnetic interaction between the impurity local…
Conductance fluctuation is usually unavoidable in graphene nanoribbons (GNR) due to the presence of disorder along its edges. By measuring the low-frequency noise in GNR devices, we find that the conductance fluctuation is strongly…
We measure and analyze noise-induced energy-fluctuations of spin qubits defined in quantum dots made of isotopically natural silicon. Combining Ramsey, time-correlation of single-shot measurements, and CPMG experiments, we cover the qubit…
We study the effect that the ferromagnetic order has on the electrical properties of Diluted Magnetic Semiconductors. We analyze the temperature dependence of the dielectric constant and of the resistivity of Ga$_{1-x}$Mn$_x$As. In our…
Low frequency noise in current biased La$_{0.82}$Ca$_{0.18}$MnO$_{3}$ single crystals has been investigated in a wide temperature range from 79 K to 290 K. Despite pronounced changes in magnetic properties and dissipation mechanisms of the…
Frequency instability of superconducting resonators and qubits leads to dephasing and time-varying energy-loss and hinders quantum-processor tune-up. Its main source is dielectric noise originating in surface oxides. Thorough noise studies…
Fluctuations of the magnetization in spin valves are shown to cause resistance noise that strongly depends on the magnetic configuration. Due to the applied external field and the dynamic exchange interaction through the normal metal…
We discuss intrinsic mechanisms of nonequilibrium excess noise in superconducting devices and transition edge sensors. In particular, we present an overview of fluctuation-driven contributions to the current noise in the vicinity of the…
We suggest an approach to account for spatial (composition) and thermal fluctuations in "disordered" magnetic models (e.g. Heisenberg, Ising) with given spatial dependence of magnetic spin-spin interaction. Our approach is based on…
Clusters of interacting two-level-systems (TLS),likely due to $F^+$ centers at the metal-insulator interface, are shown to self consistently lead to $1/f^{\alpha }$ magnetization noise in SQUIDs. By introducing a correlation-function…
Two-dimensional electron or hole systems in semiconductors offer the unique opportunity to investigate the physics of strongly interacting fermions. We have measured the 1/f resistance noise of two-dimensional hole systems in high mobility…
Influence of disorder on the ferromagnetic phase transition in diluted (III,Mn)V semiconductors is investigated analytically. The regime of small disorder is addressed, and the enhancement of the critical temperature by disorder is found…
Critical fluctuations play a fundamental role in determining the spin orders for low-dimensional quantum materials, especially for recently discovered two-dimensional (2D) magnets. Here we employ the quantum decoherence imaging technique…
The frequency stability of nanomechanical resonators (NMR) dictates the performance level of many state-of-the-art sensors (e.g., mass, force, temperature, radiation) that relate an external physical perturbation to a resonance frequency…