Mahya Khorramshahi
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Mahya Khorramshahi has a total of 12 co-authors. Here are the top co-authors by number of shared publications:
- Christian Kübel
Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
1 shared publication - Ioan Mihai Pop
IQMT, Karlsruhe Institute of Technology, Karlsruhe, Germany
1 shared publication - Lucas Brauch
IQMT, Karlsruhe Institute of Technology 1 , 76131 Karlsruhe
1 shared publication Martin Spiecker
Karlsruhe Institute of Technology
1 shared publication- Nicolas Gosling
IQMT, Karlsruhe Institute of Technology, Karlsruhe, Germany
1 shared publication Nicolas Zapata
Karlsruhe Institute of Technology
1 shared publication
Latest Publications
- Open Access
- 27 August 2025
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 24 (2)
High-impedance granular-aluminum ring resonators
Superconducting inductors with impedance surpassing the resistance quantum, i.e., superinductors, are important for quantum technologies because they enable the development of protected qubits, enhance coupling to systems with small electric dipole moments, and facilitate the study of phase-slip physics. We demonstrate superinductors with densely packed meandered traces of granular aluminum ( grAl ) with inductances up to 4 µH, achieving impedances exceeding 100 k in the 4–8 GHz range. Ring resonators made with grAl meandered superinductors exhibit quality factors on the order of 10 5 in the single-photon regime, and low nonlinearity on the order of tens of hertz. Depending on the grAl resistivity, at 10 Hz, we measure frequency-noise spectral densities in the range of 10 2 – 10 3 Hz / Hz . In some devices, in the single-photon regime, we observe a positive Kerr coefficient of unknown origin. Using more complex fabrication, the devices could be released from the substrate, either freestanding or suspended on a membrane, thereby further improving their impedance by a factor of 3.
- 27 August 2025
- Published by American Physical Society (APS) in Physical Review Applied
- Vol. 24 (2)
Open AccessHigh-impedance granular-aluminum ring resonators
Superconducting inductors with impedance surpassing the resistance quantum, i.e., superinductors, are important for quantum technologies because they enable the development of protected qubits, enhance coupling to systems with small electric dipole moments, and facilitate the study of phase-slip physics. We demonstrate superinductors with densely packed meandered traces of granular aluminum ( grAl ) with inductances up to 4 µH, achieving impedances exceeding 100 k in the 4–8 GHz range. Ring resonators made with grAl meandered superinductors exhibit quality factors on the order of 10 5 in the single-photon regime, and low nonlinearity on the order of tens of hertz. Depending on the grAl resistivity, at 10 Hz, we measure frequency-noise spectral densities in the range of 10 2 – 10 3 Hz / Hz . In some devices, in the single-photon regime, we observe a positive Kerr coefficient of unknown origin. Using more complex fabrication, the devices could be released from the substrate, either freestanding or suspended on a membrane, thereby further improving their impedance by a factor of 3.