相关论文: Macroscopic quantum tunneling in PdO nanoparticles
Fragile quantum effects such as single electron charging in quantum dots or macroscopic coherent tunneling in superconducting junctions are the basis of modern quantum technologies. These phenomena can only be observed in devices where the…
The structural phase transition in hexagonal BaMnO$_3$ occurring at $T_c$=130 K was studied in ceramic samples using electron and X-ray diffraction, second harmonic generation as well as by dielectric and lattice dynamic spectroscopies. The…
Theoretically, we recently showed that the scaling relation between the transition temperature T_c and the superfluid density at zero temperature n_s (0) might exhibit a parabolic pattern [Scientific Reports 6 (2016) 23863]. It is…
The purpose of this paper is to study the thermodynamic equilibrium properties of a collection of non-interacting three-dimensional (3D) magnetically anisotropic nanoparticles in the light of classical statistical physics. Pertaining to the…
Stable and switchable polarization of ferroelectric materials opens a possibility to electrically control their functional behavior. A particularly promising approach is to employ ferroelectric tunnel junctions where the polarization…
We report results from Monte Carlo simulations of systems of magnetic dipoles that relax through quantum tunneling, much as Fe_8 crystals at very low temperature.For short times, a hole develops in suitably defined magnetic field…
To evaluate the self-heating effects of FeCo magnetic nanoparticles, the surface oxidized FeCo nanoparticles were synthesized by co-precipitation method with the reduction reaction without any post treatments. As-synthesized FeCo…
We present electronic transport measurements of a single wall carbon nanotube quantum dot coupled to Nb superconducting contacts. For temperatures comparable to the superconducting gap peculiar transport features are observed inside the…
We demonstrate feedback cooling of the center-of-mass motion of single charged nanoparticles to millikelvin temperatures in three dimensions via applying oscillating electric fields synchronized to their optically observed motion. The…
We have grown a YCrO$_3$ single crystal by the floating-zone method and studied its temperature-dependent crystalline structure and magnetization by X-ray powder diffraction and PPMS DynaCool measurements. All diffraction patterns were well…
We show that resonant quantum tunneling of the magnetization, until now observed only in zero-dimensional (0D) cluster systems, occurs in the molecular Ising spin chain $[(CH_3)_3NH]CoCl_3\cdot 2H_2O$, which orders as a canted…
We have studied the magnetic-field-tuned superconductivity destroying quantum transition in amorphous In-O films with the onset of superconductivity in zero field at about 2 K. At temperatures down to 30 mK the critical resistance…
We study, by means of magnetic susceptibility and magnetic aging experiments, the nature of the glassy magnetic dynamics in arrays of Co nanoparticles, self-organized in N layers from N=1 (two-dimensional limit) up to N=20…
Ni3C nanoparticles of about 40 nm have been studied experimentally to exhibit weak ferromagnetic (FM), spin-glass (SG) and paramagnetic (PM) properties. The freezing temperature of the SG phase at zero applied field is determined as, TF0 ~…
We report here enhancement of ferromagnetism in pure ZnO upon thermal annealing with the ferromagnetic transition temperature Tc above room temperature. We observe a finite coercive field upto 300K and a finite thermoremanent magnetization…
We have studied the crossover between thermally assisted and pure quantum tunneling in single crystals of high spin (S=10) uniaxial single molecule magnet Mn12-acetate using micro-Hall effect magnetometry. Magnetic hysteresis experiments…
The perpendicular magnetic anisotropy (PMA) at magnetic transition metal/oxide interfaces is a key element in building out-of-plane magnetized magnetic tunnel junctions for spin-transfer-torque magnetic random access memory (STT-MRAM). Size…
On-chip refrigeration at cryogenic temperatures is becoming an important requirement in the context of quantum technologies and nanoelectronics. Ferroic materials with enhanced electrocaloric effects at phase transitions are good material…
We perform measurements of the switching current distributions of three w = 120 nm wide, 4 nm thick NbN superconducting strips which are used for single-photon detectors. These strips are much wider than the diameter the vortex cores, so…
The thermal behavior of free and alumina-supported iron-carbon nanoparticles is investigated via molecular dynamics simulations, in which the effect of the substrate is treated with a simple Morse potential fitted to ab initio data. We…