The phrase "a popular author" is correct and usable in written English.
You can use it to describe an author who has gained widespread recognition and readership.
Example: "J.K. Rowling is a popular author known for her Harry Potter series."
Alternatives: "a well-known writer" or "a bestselling author."
JOHN GRISHAM is a popular author of novels about LEGAL EAGLES.
As for her private life, Baker was as frank as could be expected for a popular author of her time.
The 78-year-old writer was a popular author in Azerbaijan until the release of his 2012 novella Stone Dreams.
His friend, Hussain Zaidi, is a popular author of crime fiction, which he bases on the stories he learned during his former career as a journalist.
Assisting him was Stephen King, a popular author who has written a novella that will be available only on the device.
Researchers learned that people would come in from the suburbs to see a popular author, but not just to buy a book, Ms. Seajay said.
Haeckel was a scientist who went on to become a prolific popular author.
On the first occasion, as a bookshop, the company entered the market with a popular work of an already popular author.
And then to make it more reader-friendly, HarperCollins had a more popular author go through it".
Minchin at Puffin added that it was "a great shame that a school would see fit not to give their pupils the opportunity to explore their beliefs and to engage with such universal issues as religion with a hugely popular author of Meg's calibre.
How puzzling that Thomas Mann should be interested in Hemingway, who, in my vague idea of him, was a very popular author of novels that had been made into romantic movies (I loved Ingrid Bergman, I loved Humphrey Bogart) and wrote about fishing and boxing (I hated sports).
