Physics Colloquium: Dr. Dafei Jin, Argonne National Laboratory


Location: 118 Nieuwland Science Hall (View on map )

Quantum computing, transduction, and sensing by quantum devices in quantum matter

Dr. Dafei Jin
Scientist, Nanoscience
Argonne National Laboratory

In this colloquium, I will introduce a series of our latest studies on fabricating and utilizing superconducting quantum devices in condensed quantum fluids and solids for a variety of applications across quantum information science, including quantum computing, transduction, and sensing.

First, I will present our experimental realization of a new quantum-bit (qubit) platform based upon isolated single electrons trapped on an ultraclean solid-neon surface in vacuum. By on-chip integrating an electrostatic trap and a superconducting quantum  circuit at 10mK temperature, we achieve for the first time strong coupling between a single electron and a single microwave photon. Qubit gate control and dispersive readout are successfully demonstrated. The measured energy relaxation time and phase coherence time indicate that the electron-on-solid-neon qubit already performs near the state of the art as a charge qubit.

Next, I will present our theoretical prediction and experimental progress on revealing the spacetime crystalline order in a parametrically driven (Floquet) high-Tc superconductor BSCCO. We aim to use the associated robust and coherent half-harmonic generation in the 0.1-10THz frequency range to transduce quantum information between 10GHz-scale microwave photons in a local quantum computer and 200THz-scale telecom photons in a long-distance quantum network.

Lastly, I will present our experimental development of an infrared laser-scanning microscopy and a superconducting transition edge sensor (TES) with a superconducting quantum interference device (SQUID) to measure the quasiparticle diffusion in a superconducting aluminum receiver immersed in superfluid helium-4 below 100mK. This endeavor constitutes an essential part of the DOE-funded SPICE/HeRALD Multi-institution Collaboration, the goal of which is to sense keV-to-GeV low-mass dark matter.

Hosted by Prof. Mathews