Aluminum (Al)
=============


       
      

**Superconducting Materials**

 

The Workhorse of Superconducting Qubits

**Tc = 1.2 K**

 

Aluminum (Al)
-------------

The Workhorse of Superconducting Qubits

 **Role in quantum circuits** 

Qubit body, Josephson junction electrodes, resonators, coplanar waveguides

 **Why it matters** 

Aluminum's native oxide (AlOx) forms a reproducible ~1–2 nm tunnel barrier for Josephson
            junctions — the heart of every superconducting qubit. Its long coherence times and
            CMOS-compatible deposition make it one of the most practical materials for scalable
            superconducting qubit fabrication.

 **Key facts** 
* Type I superconductor — minimal trapped flux vortices
* Naturally forms AlOx tunnel barrier (~1–2 nm thick)
* Shadow evaporation enables precise Josephson junction fabrication
* Compatible with scalable superconducting qubit fabrication workflows
* Low decoherence from TLS defects when surface is clean