What is the name of Beyoncé's alter ego introduced during her I Am... era?

Beyoncé's alter ego introduced during her I Am... era was Sasha Fierce. She described Sasha as a more confident, glamorous, and performance-focused persona.

The concept shaped the double album I Am... Sasha Fierce, released in 2008. One disc emphasized personal and emotional songs, while the other presented the bold stage character associated with Sasha Fierce.

The album included songs such as “If I Were a Boy,” “Halo,” “Single Ladies (Put a Ring on It),” and “Diva.” These tracks showed contrasting sides of Beyoncé's artistic image and helped make the project one of her most commercially successful releases.

Beyoncé later said that she no longer needed to separate herself from the persona because she had matured and could embody those qualities herself. The name therefore belongs specifically to a period and concept in her career, not to a separate performer.