相关论文: Low-temperature, high-resolution magnetic force mi…
We have developed a mini-coil pulsed magnet system with direct optical access, ideally suited for nonlinear and ultrafast spectroscopy studies of materials in high magnetic fields up to 30 T. The apparatus consists of a small coil in a…
We present a probe-type scanning tunneling microscope (STM) with atomic resolution that is designed to be directly inserted and work in a harsh vibrational cryogen-free superconducting magnet system. When a commercial variable temperature…
Phase coexistence across disorder-broadened and magnetic-field-induced first order antiferromagnetic to ferrimagnetic transition in polycrystalline $Mn_{1.85}Co_{0.15}Sb$ has been studied mesoscopically by Scanning Hall Probe Microscope at…
Neutron powder diffraction studies of the crystal and magnetic structures of the magnetocaloric compound Mn1.1Fe0.9(P0.8Ge0.2) have been carried out as a function of temperature, applied magnetic field, and pressure. The data reveal that…
Near-field force measurements at submicron separations can probe Casimir effects and hypothetical short-range interactions, but require cryogenic operation and stable, \textit{in situ} control of separation-dependent backgrounds. We propose…
We present a permanent magnet arrangement that can achieve a tuneable axial magnetic field from 1.80(8)-2.67(2) kG along the z-axis, where (x,y) = (0,0), with a rms field variation of less than 1% over a length of 25 mm. The instrument…
An instrument has been constructed to measure a large range of magnetostriction and thermal expansion between room temperature and 4 K in a superconductive split-coil magnet, that allows investigation in magnetic fields up to 12 T. The very…
We use a sensitive magneto-optical microscopy technique to image the magnetization response of micron-scale ferromagnetic disks to changes in applied magnetic field. This differential technique relies on a modulated applied magnetic field…
Magneto-optical sensors including spin noise spectroscopies and magneto-optical Kerr effect microscopies are now ubiquitous tools for materials characterization that can provide new understanding of spin dynamics, hyperfine interactions,…
Mechanical properties of biological samples have been imaged with a \textit{Force Feedback Microscope}. Force, force gradient and dissipation are measured simultaneously and quantitatively, merely knowing the AFM cantilever spring constant.…
Magnetic anisotropy encodes key information about the free-energy landscape of magnetic materials, but its quantitative characterization often requires probes beyond conventional magnetometry. A quartz tuning-fork resonator provides direct…
We present the design and operation of a fiber-based cryogenic confocal microscope. It is designed as a compact cold-finger that fits inside the bore of a superconducting magnet, and which is a modular unit that can be easily swapped…
Ultra-low field (ULF) MRI is a promising method for inexpensive medical imaging with various additional advantages over conventional instruments such as low weight, low power, portability, absence of artifacts from metals, and high…
We examine the potential of polarization bispectra of the cosmic microwave background (CMB) to constrain primordial magnetic fields (PMFs). We compute all possible bispectra between temperature and polarization anisotropies sourced by PMFs…
We present a combined scanning force and tunneling microscope working in a dilution refrigerator that is optimized for the study of individual electronic nano-devices. This apparatus is equipped with commercial piezo-electric positioners…
We report the development of a scanning force microscope based on an ultra-sensitive silicon nitride membrane transducer. Our development is made possible by inverting the standard microscope geometry - in our instrument, the substrate is…
Recent advances in nanoscale magnetism have demonstrated the potential for spin-based technology including magnetic random access memory, nanoscale microwave sources, and ultra-low power signal transfer. Future engineering advances and new…
We present here the design of a sensitive Compact Faraday-modulator (CFM) based optical magnetometer for imaging the distribution of weak local magnetic fields inside hysteretic magnetic materials. The system developed has a root mean…
Magnetic field sensors with high sensitivity and spatial resolution have profoundly impacted diverse applications ranging from geo-positioning and navigation to medical imaging, materials science, and space exploration. However, the use of…
Quantum mechanics has so far not been tested for mechanical objects at the scale of the Planck mass $\sqrt{\hbar c/ G} \simeq 22\,\mu\mathrm{g}$. We present an experiment where a 1 mm quartz micropillar resonating at 3.6 MHz with an…