Techniques
Pulsed Laser Deposition
This is a non-equilibrium physical vapor deposition (PVD) technique, which utilizes intense nano-second long laser pulses to ablate materials. The laser-material interaction leads to quasi-instantaneous melting, vaporization, and ionization of the target material, forming the so-called "plasma plume". The plasma plume expands away from the target towards the substrate (typically an oriented crystal) and condensates atop to form the film. The beauty of this technique is that regardless of chemical composition, the "quasi-instantaneous" vaporization of the target material enables a stoichiometric transfer of material to the film. We employ this technique as our primary tool for growing thin film heterostructures. Click here to learn more about this technique.
Scanning probe microscopy
This is our "all-weather'' meteorology tool that we use for primitive surface characterization to the advanced electrical characterization of ferroelectricity, flexoelectricity, and local I-V . Click here to learn more about this technique.
Device fabrication
Using UV photolithography/electron beam lithography, plasma etching, and sputtering techniques, we make devices with a typical feature size of ~ 1 um.
Spin-torque Ferromagnetic Resonance
As the name goes, this technique utilizes ferromagnetic resonance, where the magnetization of a ferromagnetic layer precesses in response to the torque exerted by a spin current. As a result, the resistance of the ferromagnet oscillates to produce a finite voltage signal. Measuring this voltage using lock-in enables characterizing the charge-spin conversion via spin Hall or Rashba Edelstein effect. Click here to learn more about this technique.
Transport and magnetic characterization
We employ standard transport (w and w/o a magnetic field) and magnetization (VSM) measurements for basic electrical and magnetic characterization of thin films.
Useful Software
GenX
A versatile GUI based open source software for fitting X-ray and Neutron reflectivity data. This software can be used for structural and magnetic characterization of thin films. Click here to find the link of this software.
Gwyddion
An open source software for analyzing scanning probe force microscopy data. This software supports reading/processing binary data files from any commercially available scanning probe microscope! Click here to find the link of this software.