Abstract As quantum computing evolves from the multi‐qubit stage to large multimodularprocessors, addressability and scalability of quantum hardware will require 3D integration and packaging. The advancement of flip‐chip technology is critical to enabling progress in this area. However, various types of coupling, such as capacitive, inductive, and galvanic, still require systematic research into the principles, quantification, and loss mechanisms. In this article, different types of 3D architecture are examined using flip‐chip technology. The and superconducting resonators with qubit circuits are designed in a modular configuration consisting of two silicon substrates. This arrangement allows numerical analysis and systematic experimental investigation of capacitive, inductive, and galvanic coupling mechanisms. The transmission of short control pulses for fast qubit manipulation is demonstrated and the feasibility of quantum state transfer is theoretically explored, highlighting the potential of this approach for scalable quantum processors. Particular focus is also on the fabrication technology of superconducting indium bumps between silicon substrates.Abstract As quantum computing evolves from the multi‐qubit stage to large multimodularprocessors, addressability and scalability of quantum hardware will require 3D integration and packaging. The advancement of flip‐chip technology is critical to enabling progress in this area. However, various types of coupling, such as capacitive, inductive, and galvanic, still require systematic research into the principles, quantification, and loss mechanisms. In this article, different types of 3D architecture are examined using flip‐chip technology. The and superconducting resonators with qubit circuits are designed in a modular configuration consisting of two silicon substrates. This arrangement allows numerical analysis and systematic experimental investigation of capacitive, inductive, and galvanic coupling mechanisms. The transmission of short control pulses for fast qubit manipulation is demonstrated and the feasibility of quantum state transfer is theoretically explored, highlighting the potential of this approach for scalable quantum processors. Particular focus is also on the fabrication technology of superconducting indium bumps between silicon substrates.

Advanced Quantum TechnologiesJul 9, 20250 citations

3D Integrated Embedded Filters for Superconducting Quantum Circuits

Waqas Ahmad, Gioele Consani, Mohammad Tasnimul Haque +2 more

Microwave filtering for superconducting qubits is a key element of quantum computing technology, enabling high coherence and fast state detection. This work presents the design and implementation of novel microwave Purcell filters for superconducting quantum circuits, integrated within a multilayer printed circuit board (PCB). The off-chip design removes all filter components from the qubit substrate, reducing device complexity, improving layout footprint and allowing better scalability to large qubit counts. Each embedded filter can couple up to nine readout resonators, enabling efficient multiplexed readout. Electromagnetic simulations of the filter predict a thousand-fold improvement in qubit isolation from the readout port. The design was experimentally validated under cryogenic conditions in conjunction with a 35-qubit device, demonstrating compatibility of the PCB-based filter with high-coherence superconducting qubits. The comparison of the measured qubit median T1 of 84 $μ$ s with the expected radiative limit from electromagnetic simulations validated the presence of Purcell filtering in the system.Microwave filtering for superconducting qubits is a key element of quantum computing technology, enabling high coherence and fast state detection. This work presents the design and implementation of novel microwave Purcell filters for superconducting quantum circuits, integrated within a multilayer printed circuit board (PCB). The off-chip design removes all filter components from the qubit substrate, reducing device complexity, improving layout footprint and allowing better scalability to large qubit counts. Each embedded filter can couple up to nine readout resonators, enabling efficient multiplexed readout. Electromagnetic simulations of the filter predict a thousand-fold improvement in qubit isolation from the readout port. The design was experimentally validated under cryogenic conditions in conjunction with a 35-qubit device, demonstrating compatibility of the PCB-based filter with high-coherence superconducting qubits. The comparison of the measured qubit median T1 of 84 $μ$s with the expected radiative limit from electromagnetic simulations validated the presence of Purcell filtering in the system.

quant-pharXiv:2602.24003Mar 2, 20260 citations

Design and characterization of a multi-qubit circuit for quantum simulations

Vinay Ramasesh, Kevin M. O'Brien, Allison Dove +3 more

Bulletin of the American Physical SocietyMar 13, 20174 citations

μ

s with the expected radiative limit from electromagnetic simulations validated the presence of Purcell filtering in the system.