Publications
Anisotropic Gigahertz Antiferromagnetic Resonances of the Easy-Axis van der Waals Antiferromagnet CrSBr
We report measurements of antiferromagnetic resonances in the van der Waals easy-axis antiferromagnet CrSBr. The interlayer exchange field and magnetocrystalline anisotropy fields are comparable to laboratory magnetic fields, allowing a rich variety of gigahertz-frequency dynamical modes to be accessed. By mapping the resonance frequencies as a function of the magnitude and angle of applied magnetic field, we identify the different regimes of antiferromagnetic dynamics.
Engineered dissipation for quantum information science
Quantum information processing relies on the precise control of non-classical states in the presence of many uncontrolled environmental degrees of freedom. The interactions between the relevant degrees of freedom and the environment are often viewed as detrimental, as they dissipate energy and decohere quantum states. Nonetheless, when controlled, dissipation is an essential tool for manipulating quantum information: dissipation engineering enables quantum measurement, quantum-state preparation and quantum-state stabilization.
Programming interactions in magnetic handshake materials
The ability to rapidly manufacture building blocks with specific binding interactions is a key aspect of programmable assembly. Recent developments in DNA nanotechnology and colloidal particle synthesis have significantly advanced our ability to create particle sets with programmable interactions, based on DNA or shape complementarity. The increasing miniaturization underlying magnetic storage offers a new path for engineering programmable components for self assembly, by printing magnetic dipole patterns on substrates using nanotechnology.
Conversion Between 3 He Melting Curve Scales Below 100 mK
We provide the conversion parameters to allow a 3He melting curve thermometer to be used to calibrate secondary thermometers to the PLTS2000 temperature scale (Rusby et al. in J Low Temp Phys 149(3):156, 2007). Additional fits to the phase diagram of superfluid 3He are also provided using the melting curve P, T measurements and of the phase diagram of superfluid 3He (Greywall in Phys Rev B 33(11):7520, https://doi.org/10.1103/PhysRevB.33.7520, 1986) as a bridge.
Moiré coupling and other emergent phenomena in stacked van der Waals materials
Strong increase in ultrasound attenuation below Tc in Sr2 RuO4: Possible evidence for domains
Recent experiments suggest that Sr2RuO4 has a two-component superconducting order parameter (OP). A two-component OP has multiple degrees of freedom in the superconducting state that can result in low-energy collective modes or the formation of domain walls-a possibility that would explain a number of experimental observations including the smallness of the signature of time reversal symmetry breaking at Tc and telegraph noise in critical current experiments. We use resonant ultrasound spectroscopy to perform ultrasound attenuation measurements across the superconducting Tc of Sr2RuO4.
Dielectric catastrophe at the Wigner-Mott transition in a moiré superlattice
The bandwidth-tuned Wigner-Mott transition is an interaction-driven phase transition from a generalized Wigner crystal to a Fermi liquid. Because the transition is generally accompanied by both magnetic and charge-order instabilities, it remains unclear if a continuous Wigner-Mott transition exists. Here, we demonstrate bandwidth-tuned metal-insulator transitions at fixed fractional fillings of a MoSe2/WS2 moiré superlattice. The bandwidth is controlled by an out-of-plane electric field. The dielectric response is probed optically with the 2s exciton in a remote WSe2 sensor layer.
Power laws in physics
Elastocaloric determination of the phase diagram of Sr2RuO4
One of the main developments in unconventional superconductivity in the past two decades has been the discovery that most unconventional superconductors form phase diagrams that also contain other strongly correlated states. Many systems of interest are therefore close to more than one instability, and tuning between the resultant ordered phases is the subject of intense research1.
Van der Waals πjosephson Junctions
Proximity-induced superconductivity in a ferromagnet can induce Cooper pairs with a finite center-of-mass momentum and stabilize Josephson junctions (JJs) with πphase difference in superconductor-ferromagnet-superconductor heterostructures. The emergence of two-dimensional layered superconducting and magnetic materials promises a new platform for realizing πJJs with atomically sharp interfaces. Here we demonstrate a thickness-driven 0-πtransition in JJs made of NbSe2(an Ising superconductor) and Cr2Ge2Te6(a ferromagnetic semiconductor).