Alp Sipahigil

:) definitely not common for one-on-one meetings. Might be ok in some time-sensitive situations (e.g. zoom interview) where it’s ok if 2-3 out 5-6 can make it, and it is recorded

Broadband and high-precision two-level system loss measurement using superconducting multi-wave resonators Two-level systems (TLS) are known to be a dominant source of dissipation and decoherence in superconducting qubits. Superconducting resonators provide a convenient way to study TLS-induced loss due to...

Very nice work from AWS:
arxiv.org/abs/2506.08130
Surprised why this approach hasn't become the norm in superconducting resonator characterization looong time ago! We focus too much on "single-photon level" resonator measurements. While what matters is the saturation electric field for TLSs.

Scary, sorry to hear… any preventive advice, like inlet pressure below a certain level?

www.nature.com/articles/d41...

Multiplexed color centers in a silicon photonic cavity array Entanglement distribution is central to the modular scaling of quantum processors and establishing quantum networks. Color centers with telecom-band transitions and long spin coherence times are suita...

We demonstrate multiplexed single-photon generation from T centers in a silicon photonic cavity array, and probe waveguide-mediated long-range interactions using a single emitter.

arxiv.org/abs/2501.17339

Congrats to the entire team! Comments welcomed.

These observations indicate the possibility of miniaturizing qubits and improving their performance by codesigning their phonon environment.

Congrats to Mutasem Odeh and the team for the nice work!

Non-Markovian dynamics of a superconducting qubit in a phononic bandgap - Nature Physics Defects known as two-level systems are a major source of noise for superconducting qubits. Adding a phononic crystal is now shown to extend the lifetime of these two-level systems, which could lead to...

New group paper!

We show that embedding a superconducting qubit in a phononic bandgap metamaterial modifies TLS dissipation to a non-Markovian regime.

www.nature.com/articles/s41...

Acceptor-Induced Bulk Dielectric Loss in Superconducting Circuits on Silicon Boron acceptors in the silicon substrates of superconducting qubits act as atomic-scale defects that can lead to qubit decay.

If you are interested in understanding the microscopic origins of TLSs (journals.aps.org/prx/abstract...) and developing phononic mitigation strategies (arxiv.org/abs/2312.01031), please reach out!

Please share with anyone that might be interested! Eligibility: US citizens

IC postdoc fellowship opportunity on defect engineering for superconducting qubits:
www.zintellect.com/Opportunity/...

Cal bears logo made from illuminated dots on a black background.

🧪Constrained optimization tiling of the Cal bears logo, using simulated differential phase-contrast imaging of strontium titanate atoms.

🔬 Captured for @molecularfoundry.bsky.social #Nano Art Contest.

📷 Georgios Varnavides, @ucberkeleyofficial.bsky.social

More: foundry.lbl.gov/2024/10/21/a...