| AVS 66th International Symposium & Exhibition | |
| Materials and Processes for Quantum Information, Computing and Science Focus Topic | Monday Sessions |
| Session QS+EM+MN+NS-MoM |
| Session: | High Coherence Qubits for Quantum Computing |
| Presenter: | Ruichen Zhao, National Institute of Standards and Technology (NIST) |
| Authors: | R. Zhao, National Institute of Standards and Technology (NIST) M. Bal, National Institute of Standards and Technology (NIST) J.L. Long, National Institute of Standards and Technology (NIST) R.E. Lake, National Institute of Standards and Technology (NIST) X. Wu, National Institute of Standards and Technology (NIST) C. Rae McRae, National Institute of Standards and Technology (NIST) H.-S. Ku, National Institute of Standards and Technology (NIST) H. Wang, National Institute of Standards and Technology (NIST) D.P. Pappas, National Institute of Standards and Technology (NIST) |
| Correspondent: | Click to Email |
Josephson junctions (JJs) are the power horses that drive the development of superconducting quantum technologies in the past decades. The non-linear inductance of JJs turns superconducting circuitry into a high-coherence two-level system that forms the foundation for quantum information processing [1]. They also enable Josephson parametric amplification that significantly improves the measurement of the fragile quantum state of superconducting qubits, mechanical oscillators or spins [2]. Consequently, the characterization of junction inductance becomes essential for the design and fabrication of these superconducting quantum devices.
Here, we present a systematic approach to characterize the micron-size JJs made from a new process. This new recipe extends from our previous work on nanoscale overlapping qubit junctions [1]. First, we collect statistics of the normal-state resistance over 2000 JJs through the room-temperature automated probing test. Second, we use Ambegaokar-baratoff formula to map the normal-state junction resistance into Josephson inductance [3]. Then we extract and investigate the process bias of our JJs. Based on this new information of JJs variation, we proposed a new JJ process which could potentially provide better control over the Junction inductance and therefore, deliver more reliable parameters for the device design.
[1] X. Wu, et al. "Overlap junctions for high coherence superconducting qubits." Applied Physics Letters 111.3: 032602 (2017).
[2] M. Malnou, et al. Optimal operation of a Josephson parametric amplifier for vacuum squeezing. Physical Review Applied, 9(4), 044023 (2018).
[3] V. Ambegaokar, & A. Baratoff, “Tunneling between superconductors.” Physical Review Letters, 10(11), 486 (1963).