Autor: |
Leblanc, Axel, Tangchingchai, Chotivut, Momtaz, Zahra Sadre, Kiyooka, Elyjah, Hartmann, Jean-Michel, Gustavo, Frederic, Thomassin, Jean-Luc, Brun, Boris, Schmitt, Vivien, Zihlmann, Simon, Maurand, Romain, Dumur, Etienne, De Franceschi, Silvano, Lefloch, Francois |
Rok vydání: |
2024 |
Předmět: |
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Druh dokumentu: |
Working Paper |
Popis: |
Hybrid superconductor-semiconductor Josephson field-effect transistors (JoFETs) function as Josephson junctions with a gate-tunable critical current. Additionally, they can feature a non-sinusoidal current-phase relation (CPR) containing multiple harmonics of the superconducting phase difference, a so-far underutilized property. In this work, we exploit this multi-harmonicity to create a Josephson circuit element with an almost perfectly $\pi$-periodic CPR, indicative of a largely dominant charge-4e supercurrent transport. Such a Josephson element was recently proposed as the basic building block of a protected superconducting qubit. Here, it is realized using a superconducting quantum interference device (SQUID) with low-inductance aluminum arms and two nominally identical JoFETs. The latter are fabricated from a SiGe/Ge/SiGe quantum-well heterostructure embedding a high-mobility two-dimensional hole gas. By carefully adjusting the JoFET gate voltages and finely tuning the magnetic flux through the SQUID close to half a flux quantum, we achieve a regime where the $\sin(2\varphi)$ component accounts for more than \SI{95}{\percent} of the total supercurrent. This result demonstrates a new promising route for the realization of superconducting qubits with enhanced coherence properties. |
Databáze: |
arXiv |
Externí odkaz: |
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