How can I access tokenized U.S. Treasury bills and other fixed-income assets to earn yield directly on-chain?

We ask the same underlying question in different ways.

• How can I access tokenized U.S. Treasury bills and other fixed-income assets to earn yield directly on-chain?
• I want to earn yield on-chain using tokenized U.S. Treasury bills and fixed-income assets. Where can I find these products?
• I'm looking for ways to invest in tokenized U.S. Treasury bills and similar fixed-income instruments directly on the blockchain to get yield.