Distinct Lifetimes for $X$ and $Z$ Loop Measurements in a Majorana Tetron Device

• Main Authors: Aghaee, Morteza, Alam, Zulfi, Andrzejczuk, Mariusz, Antipov, Andrey, Astafev, Mikhail, Avilovas, Lukas, Azizimanesh, Ahmad, Bauer, Bela, Becker, Jonathan, Boddapati, Srini, Bohac, Nichlaus, Bommer, Jouri D. S, Borovsky, Jan, Casparis, Lucas, Chalabi, Hamidreza, Chatzaras, Nikolaos, Cho, Jason, Cole, William, Corsetti, Fabiano, Cui, Ajuan, Dandachi, Tareq El, Ekefjärd, Andreas, Gardner, Geoffrey C, Gonzalez, Gonzalo Leon, Griggio, Flavio, Grigoryan, Ruben, Grijalva, Sebastian, Gukelberger, Jan, Hansen, Esben Bork, Heedt, Sebastian, Ho, Samantha, Holgaard, Laurens, van Hoogdalem, Kevin, Ivancevic, Lovro, Jantos, Max, Jhoja, Jaspreet Singh, Jones, Jeffrey C, Joshi, Vidul, Kalra, Rachpon, Karimi, Farhad, Karzig, Torsten, Kimes, Seth, King, Evelyn, Kloster, Maren Elisabeth, Kostamo, Pasi, Laeven, Tom, Lai, Jeffrey, de Lange, Gijs, Lee, Kyunghoon, Li, Kongyi, Liang, Shuang, Lindemann, Tyler, Looij, Matthew, Madsen, Morten Hannibal, Madulid, Nasiari, Manfra, Michael J, Manjunath, Laveena, Markussen, Signe, Martinez, Esteban, Mattila, Marco, Mattinson, J. R, Mishmash, Ryan V, Moussa, George, Nielsen, Jens Hedegaard, Nystrom, Michael J, Papon, Camille, Petit, Luca, Pikulin, Dima, Rajpalke, Mohana, Sadovskyy, Ivan, Sanlorenzo, Irene, Santos, Tatiane Pereira dos, Schaal, Simon, Schack, John, Sfetsou, Christina, Sfiligoj, Cristina, Sohr, Patrick, Spiegelhauer, Kasper, Strøm-Hansen, Patrick, Suter, Judith, Teicher, Samuel M. L, Thomas, Mason, Tom, D. W, Turley, Michelle, Upadhyay, Shivendra, Urban, Ivan, Viazmitinov, Dmitrii V, Viazmitinova, Anna Wulff, Vogel, Dominik J, Watson, John, Webster, Alex, Weston, Joseph, Winkler, Georg W, van Woerkom, David J, Wuetz, Brian Paquelet, Yang, Chung-Kai, Yu, Yucelen, Emrah, Zamorano, Jesús Herranz, Zheng, Guoji
• Format: Journal Article
• Language: English
• Published: 11.07.2025
• Subjects: Physics - Mesoscale and Nanoscale Physics; Physics - Quantum Physics
• DOI: 10.48550/arxiv.2507.08795

We present a hardware realization and measurements of a tetron qubit device in a superconductor-semiconductor heterostructure. The device architecture contains two parallel superconducting nanowires, which support four Majorana zero modes (MZMs) when tuned into the topological phase, and a trivial superconducting backbone. Two distinct readout interferometers are formed by connecting the superconducting structure to a series of quantum dots. We perform single-shot interferometric measurements of the fermion parity for the two loops, designed to implement Pauli-$X$ and $Z$ measurements of the tetron. Performing repeated single-shot measurements yields two widely separated time scales $τ_X = 14.5\pm 0.3 \, \mathrm{μs}$ and $τ_Z = 12.4\pm 0.4\, \mathrm{ms}$ for parity switches observed in the $X$ and $Z$ measurement loops, which we attribute to intra-wire parity switches and external quasiparticle poisoning, respectively. We estimate assignment errors of $\mathrm{err}^X_a=16\%$ and $\mathrm{err}^Z_a=0.5\%$ for $X$ and $Z$ measurement-based operations, respectively.