Materials for Quantum Devices
In the field of materials for quantum devices, we are interested in atomic structure / decoherence relationships and how to use this information to improve processing techniques for longer coherence lifetimes and stable operation frequencies. We are applying ASAT to quantum devices to count point defects at interfaces and also using surface passivation to improve coherence lifetimes at the solid / vacuum interfaces. Below are some examples of projects we are currently working on. Applying ASAT to semiconductor, Josephson Junction, and H-depassivation lithography are sponsored by LPS.
ASAT of Planar Semiconductor Devices
Ge quantum wells grown by MBE
Gorman, B., Holtz, M., Richardson, C., Gaspe, C., Supple, E., & Butera, R. (2021). 4-D STEM Analyses of Cylindrical Specimens for Atom Probe Tomography. Microscopy and Microanalysis, 27(S1), 184-186. doi:10.1017/S1431927621001276
ASAT of Josephson Junctions
Al / AlOx / Al
Epitaxial NbTiN / AlN / NbTiN
Supple, E., Holtz, M., Richardson, C., & Gorman, B. (2021). Atomic Structure of Superconducting Tunnel Junctions using STEM and APT. Microscopy and Microanalysis, 27(S1), 2460-2462. doi:10.1017/S1431927621008795
ASAT of H-Depassivation Lithography Defined Single Atom Qubits and Delta Layers
Si: B
Si: P
Si: Al
Surface Passivation for Increased Coherence Lifetimes
Josephson Junctions